1 1578 135 MEASUREMENT OF THE EFFECT OF ISHA YOGA ON CARDIAC AUTONOMIC NERVOUS SYSTEM USING SHORT-TERM HEART RATE VARIABILITY. BACKGROUND: BENEFICIAL EFFECTS OF YOGA HAVE BEEN POSTULATED TO BE DUE TO MODULATION OF THE AUTONOMIC NERVOUS SYSTEM. OBJECTIVE: TO ASSESS THE EFFECT OF ISHA YOGA PRACTICES ON CARDIOVASCULAR AUTONOMIC NERVOUS SYSTEM THROUGH SHORT-TERM HEART RATE VARIABILITY (HRV). DESIGN OF THE STUDY: SHORT-TERM HRV OF LONG-TERM REGULAR HEALTHY 14 (12 MALES AND 2 FEMALES) ISHA YOGA PRACTITIONERS WAS COMPARED WITH THAT OF AGE- AND GENDER-MATCHED 14 (12 MALES AND 2 FEMALES) NON-YOGA PRACTITIONERS. METHODS AND MATERIALS: ECG LEAD II AND RESPIRATORY MOVEMENTS WERE RECORDED IN BOTH GROUPS USING POLYRITE DURING SUPINE REST FOR 5 MIN AND CONTROLLED DEEP BREATHING FOR 1 MINUTE. FREQUENCY DOMAIN ANALYSIS [RR INTERVAL IS THE MEAN OF DISTANCE BETWEEN SUBSEQUENT R WAVE PEAKS IN ECG], LOW FREQUENCY (LF) POWER, HIGH FREQUENCY (HF) POWER, LF NORMALIZED UNITS (NU), HF NU, LF/HF RATIO] AND TIME DOMAIN ANALYSIS [STANDARD DEVIATION OF NORMAL TO NORMAL INTERVAL (SDNN), SQUARE OF MEAN SQUARED DIFFERENCE OF SUCCESSIVE NORMAL TO NORMAL INTERVALS (RMSSD), NORMAL TO NORMAL INTERVALS WHICH ARE DIFFERING BY 50 MS (NN50), AND PERCENTAGE OF NN50 (PNN50)] OF HRV VARIABLES WERE ANALYZED FOR SUPINE REST. TIME DOMAIN ANALYSIS WAS RECORDED FOR DEEP BREATHING. RESULTS: RESULTS SHOWED STATISTICALLY SIGNIFICANT DIFFERENCES BETWEEN ISHA YOGA PRACTITIONERS AND CONTROLS IN BOTH FREQUENCY AND TIME DOMAIN ANALYSES OF HRV INDICES, WITH NO DIFFERENCE IN RESTING HEART RATE BETWEEN THE GROUPS. CONCLUSIONS: PRACTITIONERS OF ISHA YOGA SHOWED WELL-BALANCED BENEFICIAL ACTIVITY OF VAGAL EFFERENTS, AN OVERALL INCREASED HRV, AND SYMPATHOVAGAL BALANCE, COMPARED TO NON-YOGA PRACTITIONERS DURING SUPINE REST AND DEEP BREATHING.	2012	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
2  350  68 ASSESSMENT OF CARDIAC AUTONOMIC TONE FOLLOWING LONG SUDARSHAN KRIYA YOGA IN ART OF LIVING PRACTITIONERS. OBJECTIVE: THE BREATHING PROCESSES ARE KNOWN TO MODULATE CARDIAC AUTONOMIC TONE AND IMPROVE PSYCHOLOGICAL STATUS. WE INVESTIGATED CARDIAC AUTONOMIC TONE FOLLOWING LONG SUDARSHAN KRIYA YOGA (SKY) USING HEART RATE VARIABILITY (HRV) AND SKIN CONDUCTANCE LEVEL (SCL). METHODS: THIRTY HEALTHY VOLUNTEERS (AGE 28.3 +/- 8.4 YEARS; 23 M: 7 F) PARTICIPATED IN THE STUDY. ELECTROCARDIOGRAM (ECG) AND SCL WERE RECORDED FOR 5 MIN EACH, BEFORE AND AFTER LONG SKY. LONG SKY IS A COMBINATION OF PRANAYAMA AND CYCLIC RHYTHMIC BREATHING AND IS PERFORMED BY FOLLOWING THE GUIDED AUDIO INSTRUCTIONS. HRV ANALYSIS WAS USED FOR THE ASSESSMENT OF CARDIAC AUTONOMIC TONE. TIME AND FREQUENCY DOMAIN PARAMETERS OF HRV WERE CALCULATED BY USING RR INTERVAL OF ECG. SCL WAS ACQUIRED USING GALVANIC SKIN RESPONSE (GSR) AMPLIFIER OF POWERLAB IN MICROSEIMENS (MUS). RESULTS: TIME DOMAIN PARAMETERS OF HRV, INCLUDING MEAN RR INTERVAL (P = 0.000), RESPIRATORY SINUS ARRHYTHMIA (RSA) (P = 0.037), STANDARD DEVIATION OF ALL NN INTERVALS (SDNN) (P = 0.013), NN50 COUNT DIVIDED BY THE TOTAL NUMBER OF ALL NN INTERVALS (PNN50) (P = 0.004), AND SQUARE ROOT OF THE MEAN OF THE SUM OF THE SQUARES OF DIFFERENCES BETWEEN ADJACENT NN INTERVALS (RMSSD) (P = 0.002) INCREASED, AND MEAN HEART RATE DECREASED (P = 0.000) FOLLOWING LONG SKY. IN FREQUENCY DOMAIN ANALYSIS, POWER OF LOW-FREQUENCY (LF) COMPONENT (P = 0.010) AND LF/HF RATIO (P = 0.008) DECREASED SIGNIFICANTLY, WHEREAS POWER OF HIGH FREQUENCY (HF) SIGNIFICANTLY INCREASED (P = 0.010). SCL DECREASED FOLLOWING LONG SKY, ALTHOUGH IT DID NOT ATTAIN STATISTICAL SIGNIFICANCE. CONCLUSIONS: THE RESULTS SUGGEST THAT LONG SKY INDUCES SIGNIFICANT OSCILLATIONS IN CARDIAC AUTONOMIC TONE. PARASYMPATHETIC ACTIVITY INCREASES AND SYMPATHETIC ACTIVITY DECREASES AND SYMPATHOVAGAL BALANCE IMPROVES FOLLOWING LONG SKY. DECREASE IN SYMPATHETIC ACTIVITY IS ALSO DEMONSTRATED BY DECREASE IN CONDUCTANCE ALTHOUGH IT DID NOT REACH STATISTICAL SIGNIFICANCE. FROM THIS STUDY IT CAN BE CONCLUDED THAT LONG SKY HAS A BENEFICIAL EFFECT ON CARDIAC AUTONOMIC TONE, AND PSYCHOPHYSIOLOGICAL RELAXATION. IT MAY SERVE AS A TOOL TO IMPROVE HRV, WHICH IS THE MARKER OF CARDIOVASCULAR HEALTH.	2017	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
3  370  47 AUTONOMIC TONE AND BAROREFLEX SENSITIVITY DURING 70 DEGREES HEAD-UP TILT IN YOGA PRACTITIONERS. INTRODUCTION: THE INTERVENTION OF YOGA WAS SHOWN TO IMPROVE THE AUTONOMIC CONDITIONING IN HUMANS EVIDENT FROM THE ENHANCEMENT OF PARASYMPATHETIC ACTIVITY AND BAROREFLEX SENSITIVITY (BRS). FROM THE DOCUMENTED HEALTH BENEFITS OF YOGA, WE HYPOTHESIZED THAT THE EXPERIENCE OF YOGA MAY RESULT IN ADAPTATION TO THE ORTHOSTATIC STRESS DUE TO ENHANCED BRS. AIM: TO DECIPHER THE EFFECTS OF YOGA IN THE MODULATION OF AUTONOMIC FUNCTION DURING ORTHOSTATIC CHALLENGE. MATERIALS AND METHODS: THIS WAS A COMPARATIVE STUDY DESIGN CONDUCTED IN AUTONOMIC FUNCTION TEST LAB, OF THE DEPARTMENT OF PHYSIOLOGY, ALL INDIA INSTITUTE OF MEDICAL SCIENCES, NEW DELHI, INDIA. HEART RATE VARIABILITY (HRV), BLOOD PRESSURE VARIABILITY, AND BRS WERE ANALYZED ON FORTY NAIVE TO YOGA (NY) SUBJECTS AND FORTY YOGA PRACTITIONERS WITH AN AVERAGE AGE OF 31.08 +/- 7.31 YEARS AND 29.93 +/- 7.57 YEARS, RESPECTIVELY. ALL PARTICIPANTS WERE HEALTHY. SEVENTY DEGREES HEAD UP TILT (HUT) WAS USED AS AN INTERVENTION TO EVALUATE THE CARDIOVASCULAR VARIABILITY DURING ORTHOSTATIC CHALLENGE. RESULTS: DURING HUT, THE R-R INTERVAL (P = 0.042), ROOT MEAN SQUARE OF SUCCESIVE R-R INTERVAL DIFFERENCES (RMSSD) (P = 0.039), STANDARD DEVIATION OF INSTANTANEOUS BEAT-TO-BEAT R-R INTERVAL VARIABILITY (SD1) (P = 0.039) OF HRV, AND SEQUENCE BRS (P = 0.017) AND ALPHA LOW FREQUENCY OF SPECTRAL BRS (P = 0.002) WERE HIGHER IN THE YOGA GROUP. THE DELTA DECREASE IN RRI (P = 0.033) AND BRS (P < 0.01) WAS HIGHER IN THE YOGA GROUP THAN THE NY GROUP. CONCLUSION: THE EFFERENT VAGAL ACTIVITY AND BRS WERE HIGHER IN YOGA PRACTITIONERS. THE DELTA CHANGE (DECREASE) IN PARASYMPATHETIC ACTIVITY AND BRS WAS HIGHER, WITH RELATIVELY STABLE SYSTOLIC BLOOD PRESSURE INDICATING AN ADAPTIVE RESPONSE TO ORTHOSTATIC CHALLENGE BY THE YOGA PRACTITIONERS COMPARED TO THE NY GROUP.	2020	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
4  758  52 EFFECT OF SLOW BREATHING ON AUTONOMIC TONE & BAROREFLEX SENSITIVITY IN YOGA PRACTITIONERS. BACKGROUND & OBJECTIVES: SLOW BREATHING INCREASES PARASYMPATHETIC ACTIVITY AND BAROREFLEX SENSITIVITY (BRS) IN HEALTHY INDIVIDUALS, ALSO SIMILARLY OBSERVED IN YOGA PRACTITIONERS. PRANAYAMA WHICH IS AN IMPORTANT COMPONENT OF YOGA WHEN PRACTICED AT A SLOW PACE WAS AT A RESPIRATORY FREQUENCY OF AROUND 0.1 HZ (6 BREATHS/MIN). THEREFORE, IT WAS HYPOTHESIZED THAT YOGA PRACTITIONERS MIGHT HAVE ADAPTED TO SLOW BREATHING. THIS STUDY WAS AIMED TO DECIPHER THE ROLE OF YOGA ON CARDIOVASCULAR VARIABILITY DURING SLOW BREATHING (0.1 HZ) IN YOGA PRACTITIONERS. METHODS: A CROSS-SECTIONAL STUDY WAS UNDERTAKEN IN NAIVE-TO-YOGA INDIVIDUALS (N=40) AND YOGA PRACTITIONERS (N=40) WITH AN AVERAGE AGE OF 31.08 +/- 7.31 AND 29.93 +/- 7.57 YR, RESPECTIVELY. THE ANALYSIS OF HEART RATE VARIABILITY, BLOOD PRESSURE VARIABILITY (BPV) AND BRS DURING SPONTANEOUS AND SLOW BREATHING WAS COMPARED BETWEEN THE TWO GROUPS. RESULTS: DURING SLOW BREATHING, THE HEART RATE (P<0.01) WAS LOWER, RESPIRATORY RATE INTERVAL (P<0.05) AND PNN50 PER CENT (P=0.01) WERE HIGHER, MEAN SYSTOLIC BP (SBP) (P<0.05) AND SDSD (STANDARD DEVIATION OF SUCCESSIVE BEAT TO BEAT SYSTOLIC BLOOD PRESSURE DIFFERENCES) (P<0.01) OF SBP VARIABILITY WERE LOWER WITH SEQUENCE BRS (P<0.001) AND ALPHA LOW FREQUENCY (P<0.01) AND ALPHA HIGH FREQUENCY (P<0.001) OF SPECTRAL BRS WERE HIGHER IN YOGA PRACTITIONERS. INTERPRETATION & CONCLUSIONS: THE PRESENT STUDY INDICATED HIGHER PARASYMPATHETIC ACTIVITY AND BRS WITH LOWER SBP VARIABILITY AT REST AND DURING SLOW BREATHING IN YOGA PRACTITIONERS COMPARED TO NAIVE GROUP. FINDINGS INDICATE THAT THE SHORT-TERM PRACTICE OF SLOW BREATHING COMPLEMENTS THE AUGMENTED PARASYMPATHETIC ACTIVITY AND BRS IN THE YOGA GROUP.	2020	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
5 1441  48 INCREASED HEART RATE VARIABILITY BUT NO EFFECT ON BLOOD PRESSURE FROM 8 WEEKS OF HATHA YOGA - A PILOT STUDY. BACKGROUND: YOGA EXERCISES ARE KNOWN TO DECREASE STRESS AND RESTORE AUTONOMIC BALANCE. YET KNOWLEDGE ABOUT THE PHYSIOLOGICAL EFFECTS OF INVERSION POSTURES IS LIMITED. THIS STUDY AIMED TO INVESTIGATE THE EFFECTS OF INVERSION POSTURES (HEAD BELOW THE HEART) ON BLOOD PRESSURE (BP) AND HEART RATE VARIABILITY (HRV). METHODS: TWELVE HEALTHY WOMEN AND MEN TOOK PART IN AN 8-WEEK YOGA PROGRAM (60 MIN ONCE A WEEK). BP WAS MEASURED WITH AN AUTOMATIC OMRON MX3 OSCILLOMETRIC MONITORING DEVICE AND HRV WITH A HOLTER 24-HOUR ECG AT BASELINE AND 8 WEEKS AFTER THE INTERVENTION. RESULTS: THERE WAS NO SIGNIFICANT EFFECT OF INVERSION POSTURES ON BP. NINE OUT OF 12 PARTICIPANTS SHOWED A SIGNIFICANT INCREASE IN HRV (P < 0.05) AT NIGHT (2 HOURS) ON PNN50% (12.7 +/- 12.5 TO 18.2 +/- 13.3). THERE WERE NO SIGNIFICANT CHANGES IN OTHER HRV MEASURES SUCH AS NN50, LF, HF, LF/HF RATIO, LF NORMALIZED UNITS (N.U.), HF N.U. AND RMSSD. CONCLUSION: EIGHT WEEKS OF HATHA YOGA IMPROVED HRV SIGNIFICANTLY WHICH SUGGESTS AN INCREASED VAGAL TONE AND REDUCED SYMPATHETIC ACTIVITY.	2013	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
6  411  50 BLOOD PRESSURE AND HEART RATE VARIABILITY DURING YOGA-BASED ALTERNATE NOSTRIL BREATHING PRACTICE AND BREATH AWARENESS. BACKGROUND: PREVIOUS RESEARCH HAS SHOWN A REDUCTION IN BLOOD PRESSURE (BP) IMMEDIATELY AFTER THE PRACTICE OF ALTERNATE NOSTRIL YOGA BREATHING (ANYB) IN NORMAL HEALTHY MALE VOLUNTEERS AND IN HYPERTENSIVE PATIENTS OF BOTH SEXES. THE BP DURING ANYB HAS NOT BEEN RECORDED. MATERIAL/METHODS: PARTICIPANTS WERE 26 MALE VOLUNTEERS (GROUP MEAN AGE +/-SD, 23.8+/-3.5 YEARS). WE ASSESSED (1) HEART RATE VARIABILITY, (2) NON-INVASIVE ARTERIAL BP, AND (3) RESPIRATION RATE, DURING (A) ANYB AND (B) BREATH AWARENESS (BAW) SESSIONS. EACH SESSION WAS 25 MINUTES. WE PERFORMED ASSESSMENTS AT 3 TIME POINTS: PRE (5 MINUTES), DURING (15 MINUTES; FOR ANYB OR BAW) AND POST (5 MINUTES). A NAIVE-TO-YOGA CONTROL GROUP (N=15 MALES, MEAN AGE +/-SD 26.1+/-4.0 YEARS) WERE ASSESSED WHILE SEATED QUIETLY FOR 25 MINUTES. RESULTS: DURING ANYB THERE WAS A SIGNIFICANT DECREASE (REPEATED MEASURES ANOVA) IN SYSTOLIC BP AND RESPIRATION RATE; WHILE RMSSD (THE SQUARE ROOT OF THE MEAN OF THE SUM OF SQUARES OF DIFFERENCES BETWEEN ADJACENT NN INTERVALS) AND NN50 (THE NUMBER OF INTERVAL DIFFERENCES OF SUCCESSIVE NORMAL TO NORMAL INTERVALS GREATER THAN 50 MS) SIGNIFICANTLY INCREASED. DURING BAW RESPIRATION RATE DECREASED. IN CONTRAST, RESPIRATION RATE INCREASED DURING THE CONTROL STATE. ANYB AND BAW WERE SIGNIFICANTLY DIFFERENT (2-FACTOR ANOVA) IN RMSSD AND RESPIRATION RATE. BAW AND CONTROL WERE DIFFERENT WITH RESPECT TO RESPIRATION RATE. CONCLUSIONS: THE RESULTS SUGGEST THAT VAGAL ACTIVITY INCREASED DURING AND AFTER ANYB, WHICH COULD HAVE CONTRIBUTED TO THE DECREASE IN BP AND CHANGES IN THE HRV.	2014	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     
7 2759  43 YOGA PRACTITIONERS EXHIBIT HIGHER PARASYMPATHETIC ACTIVITY AND BAROREFLEX SENSITIVITY AND BETTER ADAPTABILITY TO 40 MM HG LOWER-BODY NEGATIVE PRESSURE. YOGA HAS BEEN SHOWN TO IMPROVE AUTONOMIC CONDITIONING IN HUMANS, AS EVIDENCED BY THE ENHANCEMENT OF PARASYM-PATHETIC ACTIVITY AND BAROREFLEX SENSITIVITY. THEREFORE, WE HYPOTHESIZED THAT THE EXPERIENCE OF YOGA MAY RESULT IN ADAPTATION TO ACUTE HEMODYNAMIC CHANGES. TO DECIPHER THE LONG-TERM EFFECTS OF YOGA ON CARDIOVASCULAR VARIABILITY, YOGA PRACTITIONERS WERE COMPARED TO YOGA-NAIVE SUBJECTS DURING EXPOSURE TO -40 MM HG LOWER-BODY NEGATIVE PRESSURE (LBNP). A COMPARATIVE STUDY WAS CONDUCTED ON 40 YOGANAIVE SUBJECTS AND 40 YOGA PRACTITIONERS WITH AN AVERAGE AGE OF 31.08 +/- 7.31 YEARS AND 29.93 +/- 7.57 YEARS, RESPECTIVELY. HEART RATE VARIABILITY, BLOOD PRESSURE VARIABILITY, BAROREFLEX SENSITIVITY, AND CORRELATION BETWEEN SYSTOLIC BLOOD PRESSURE AND RR INTERVAL WERE EVALUATED AT REST AND DURING LBNP. IN YOGA PRACTITIONERS, THE HEART RATE WAS LOWER IN SUPINE REST (P = 0.011) AND DURING LBNP (P = 0.043); THE PNN50 MEASURE OF HEART RATE VARIABILITY WAS HIGHER IN SUPINE REST (P = 0.011) AND DURING LBNP (P = 0.034). THE YOGA PRACTITIONERS' STANDARD DEVIATION OF SUCCESSIVE BEAT-TO-BEAT BLOOD PRESSURE INTERVALS OF SYSTOLIC BLOOD PRESSURE VARIABILITY WAS LOWER IN SUPINE REST (P = 0.034) AND DURING LBNP (P = 0.007), WITH HIGHER SEQUENCE BAROREFLEX SENSITIVITY (P = 0.019) AND ~ HIGH-FREQUENCY BAROREFLEX SENSITIVITY. MEAN SYSTOLIC BLOOD PRESSURE AND RR INTERVAL WERE INVERSELY CORRELATED IN THE YOGA GROUP (R = -0.317, P = 0.049). THE YOGA PRACTITIONERS EXHIBITED HIGHER PARASYMPATHETIC ACTIVITY AND BAROREFLEX SENSITIVITY WITH LOWER SYSTOLIC BLOOD PRESSURE VARIABILITY, INDICATING BETTER ADAPTABILITY TO LBNP COMPARED TO THE YOGA-NAIVE GROUP. OUR FINDINGS INDICATE THAT THE YOGA MODULE WAS HELPFUL IN CONDITIONS OF HYPOVOLEMIA IN HEALTHY SUBJECTS; IT IS PROPOSED TO BE BENEFICIAL IN CLINICAL CONDITIONS ASSOCIATED WITH SYMPATHETIC DOMINANCE, IMPAIRED BARORE-FLEX SENSITIVITY, AND ORTHOSTATIC INTOLERANCE.	2021	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
8 1089  35 EFFECTS OF YOGA ON THE AUTONOMIC NERVOUS SYSTEM, GAMMA-AMINOBUTYRIC-ACID, AND ALLOSTASIS IN EPILEPSY, DEPRESSION, AND POST-TRAUMATIC STRESS DISORDER. A THEORY IS PROPOSED TO EXPLAIN THE BENEFITS OF YOGA PRACTICES IN DIVERSE, FREQUENTLY COMORBID MEDICAL CONDITIONS BASED ON THE CONCEPT THAT YOGA PRACTICES REDUCE ALLOSTATIC LOAD IN STRESS RESPONSE SYSTEMS SUCH THAT OPTIMAL HOMEOSTASIS IS RESTORED. IT IS HYPOTHESIZED THAT STRESS INDUCES (1) IMBALANCE OF THE AUTONOMIC NERVOUS SYSTEM (ANS) WITH DECREASED PARASYMPATHETIC NERVOUS SYSTEM (PNS) AND INCREASED SYMPATHETIC NERVOUS SYSTEM (SNS) ACTIVITY, (2) UNDERACTIVITY OF THE GAMMA AMINO-BUTYRIC ACID (GABA) SYSTEM, THE PRIMARY INHIBITORY NEUROTRANSMITTER SYSTEM, AND (3) INCREASED ALLOSTATIC LOAD. IT IS FURTHER HYPOTHESIZED THAT YOGA-BASED PRACTICES (4) CORRECT UNDERACTIVITY OF THE PNS AND GABA SYSTEMS IN PART THROUGH STIMULATION OF THE VAGUS NERVES, THE MAIN PERIPHERAL PATHWAY OF THE PNS, AND (5) REDUCE ALLOSTATIC LOAD. DEPRESSION, EPILEPSY, POST TRAUMATIC STRESS DISORDER (PTSD), AND CHRONIC PAIN EXEMPLIFY MEDICAL CONDITIONS THAT ARE EXACERBATED BY STRESS, HAVE LOW HEART RATE VARIABILITY (HRV) AND LOW GABAERGIC ACTIVITY, RESPOND TO PHARMACOLOGIC AGENTS THAT INCREASE ACTIVITY OF THE GABA SYSTEM, AND SHOW SYMPTOM IMPROVEMENT IN RESPONSE TO YOGA-BASED INTERVENTIONS. THE OBSERVATION THAT TREATMENT RESISTANT CASES OF EPILEPSY AND DEPRESSION RESPOND TO VAGAL NERVE STIMULATION CORROBORATES THE NEED TO CORRECT PNS UNDERACTIVITY AS PART OF A SUCCESSFUL TREATMENT PLAN IN SOME CASES. ACCORDING TO THE PROPOSED THEORY, THE DECREASED PNS AND GABAERGIC ACTIVITY THAT UNDERLIES STRESS-RELATED DISORDERS CAN BE CORRECTED BY YOGA PRACTICES RESULTING IN AMELIORATION OF DISEASE SYMPTOMS. THIS HAS FAR-REACHING IMPLICATIONS FOR THE INTEGRATION OF YOGA-BASED PRACTICES IN THE TREATMENT OF A BROAD ARRAY OF DISORDERS EXACERBATED BY STRESS.	2012	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
9  448  59 CHANGES IN AUTONOMIC VARIABLES FOLLOWING TWO MEDITATIVE STATES DESCRIBED IN YOGA TEXTS. OBJECTIVES: IN ANCIENT YOGA TEXTS THERE ARE TWO MEDITATIVE STATES DESCRIBED. ONE IS DHARANA, WHICH REQUIRES FOCUSING, THE SECOND IS DHYANA, DURING WHICH THERE IS NO FOCUSING, BUT AN EXPANSIVE MENTAL STATE IS REACHED. WHILE AN EARLIER STUDY DID SHOW IMPROVED PERFORMANCE IN AN ATTENTION TASK AFTER DHARANA, THE AUTONOMIC CHANGES DURING THESE TWO STATES HAVE NOT BEEN STUDIED. METHODS: AUTONOMIC AND RESPIRATORY VARIABLES WERE ASSESSED IN 30 HEALTHY MALE VOLUNTEERS (GROUP MEAN AGE +/- SD, 29.1 +/- 5.1 YEARS) DURING FOUR MENTAL STATES DESCRIBED IN TRADITIONAL YOGA TEXTS. THESE FOUR MENTAL STATES ARE RANDOM THINKING (CANCALATA), NONMEDITATIVE FOCUSING (EKAGRATA), MEDITATIVE FOCUSING (DHARANA), AND EFFORTLESS MEDITATION (DHYANA). ASSESSMENTS WERE MADE BEFORE (5 MINUTES), DURING (20 MINUTES), AND AFTER (5 MINUTES), EACH OF THE FOUR STATES, ON FOUR SEPARATE DAYS. RESULTS: DURING DHYANA THERE WAS A SIGNIFICANT INCREASE IN THE SKIN RESISTANCE LEVEL (P<0.001; POST HOC ANALYSIS FOLLOWING ANOVA, DURING COMPARED TO PRE) AND PHOTO-PLETHYSMOGRAM AMPLITUDE (P<0.05), WHEREAS THERE WAS A SIGNIFICANT DECREASE IN THE HEART RATE (P<0.001) AND BREATH RATE (P<0.001). THERE WAS A SIGNIFICANT DECREASE IN THE LOW FREQUENCY (LF) POWER (P<0.001) AND INCREASE IN THE HIGH FREQUENCY (HF) POWER (P<0.001) IN THE FREQUENCY DOMAIN ANALYSIS OF THE HEART RATE VARIABILITY (HRV) SPECTRUM, ON WHICH HF POWER IS ASSOCIATED WITH PARASYMPATHETIC ACTIVITY. THERE WAS ALSO A SIGNIFICANT INCREASE IN THE NN50 COUNT (THE NUMBER OF INTERVAL DIFFERENCES OF SUCCESSIVE NN INTERVALS GREATER THAN 50 MS; P<0.001) AND THE PNN50 (THE PROPORTION DERIVED BY DIVIDING NN50 BY THE TOTAL NUMBER OF NN INTERVALS; P<0.001) IN TIME DOMAIN ANALYSIS OF HRV, BOTH INDICATIVE OF PARASYMPATHETIC ACTIVITY. CONCLUSIONS: MAXIMUM CHANGES WERE SEEN IN AUTONOMIC VARIABLES AND BREATH RATE DURING THE STATE OF EFFORTLESS MEDITATION (DHYANA). THE CHANGES WERE ALL SUGGESTIVE OF REDUCED SYMPATHETIC ACTIVITY AND/OR INCREASED VAGAL MODULATION. DURING DHARANA THERE WAS AN INCREASE IN SKIN RESISTANCE. THE CHANGES IN HRV DURING EKAGRATA AND CANCALATA WERE INCONCLUSIVE.	2013	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
10 1319  34 HEART RATE VARIABILITY, FLOW, MOOD AND MENTAL STRESS DURING YOGA PRACTICES IN YOGA PRACTITIONERS, NON-YOGA PRACTITIONERS AND PEOPLE WITH METABOLIC SYNDROME. HEART RATE VARIABILITY (HRV) AND RESPIRATORY SINUS ARRHYTHMIA ARE DIRECTLY ASSOCIATED WITH AUTONOMIC FLEXIBILITY, SELF-REGULATION AND WELL-BEING, AND INVERSELY ASSOCIATED WITH PHYSIOLOGICAL STRESS, PSYCHOLOGICAL STRESS AND PATHOLOGY. YOGA ENHANCES AUTONOMIC ACTIVITY, MITIGATES STRESS AND BENEFITS STRESS-RELATED CLINICAL CONDITIONS, YET THE RELATIONSHIP BETWEEN AUTONOMIC ACTIVITY AND PSYCHOPHYSIOLOGICAL RESPONSES DURING YOGA PRACTICES AND STRESSFUL STIMULI HAS NOT BEEN WIDELY EXPLORED. THIS EXPERIMENTAL STUDY EXPLORED THE RELATIONSHIP BETWEEN HRV, MOOD STATES AND FLOW EXPERIENCES IN REGULAR YOGA PRACTITIONERS (YP), NON-YOGA PRACTITIONERS (NY) AND PEOPLE WITH METABOLIC SYNDROME (METS), DURING MENTAL ARITHMETIC STRESS TEST (MAST) AND VARIOUS YOGA PRACTICES. THE STUDY FOUND THAT THE MAST PLACED A CARDIO-AUTONOMIC BURDEN IN ALL PARTICIPANTS WITH THE YP GROUP SHOWING THE GREATEST REACTIVITY AND THE MOST RAPID RECOVERY, WHILE THE METS GROUP HAD SIGNIFICANTLY BLUNTED RECOVERY. THE YP GROUP ALSO REPORTED A HEIGHTENED EXPERIENCE OF FLOW AND POSITIVE MOOD STATES COMPARED TO NY AND METS GROUPS AS WELL AS HAVING A HIGHER VAGAL TONE DURING ALL RESTING CONDITIONS. THESE RESULTS SUGGEST YOGA PRACTITIONERS HAVE A GREATER HOMEOSTATIC CAPACITY AND AUTONOMIC, METABOLIC AND PHYSIOLOGICAL RESILIENCE. FURTHER STUDIES ARE NOW NEEDED TO DETERMINE IF REGULAR YOGA PRACTICE MAY IMPROVE AUTONOMIC FLEXIBILITY IN NON-YOGA PRACTITIONERS AND METABOLIC SYNDROME PATIENTS. CLINICAL TRIAL NO 'ACTRN 2614001075673'.	2016	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
11 1530  53 IYENGAR YOGA INCREASES CARDIAC PARASYMPATHETIC NERVOUS MODULATION AMONG HEALTHY YOGA PRACTITIONERS. RELAXATION TECHNIQUES ARE ESTABLISHED IN MANAGING OF CARDIAC PATIENTS DURING REHABILITATION AIMING TO REDUCE FUTURE ADVERSE CARDIAC EVENTS. IT HAS BEEN HYPOTHESIZED THAT RELAXATION-TRAINING PROGRAMS MAY SIGNIFICANTLY IMPROVE CARDIAC AUTONOMIC NERVOUS TONE. HOWEVER, THIS HAS NOT BEEN PROVEN FOR ALL AVAILABLE RELAXATION TECHNIQUES. WE TESTED THIS ASSUMPTION BY INVESTIGATING CARDIAC VAGAL MODULATION DURING YOGA.WE EXAMINED 11 HEALTHY YOGA PRACTITIONERS (7 WOMEN AND 4 MEN, MEAN AGE: 43 +/- 11; RANGE: 26-58 YEARS). EACH INDIVIDUAL WAS SUBJECTED TO TRAINING UNITS OF 90 MIN ONCE A WEEK OVER FIVE SUCCESSIVE WEEKS. DURING TWO SESSIONS, THEY PRACTICED A YOGA PROGRAM DEVELOPED FOR CARDIAC PATIENTS BY B.K.S. IYENGAR. ON THREE SESSIONS, THEY PRACTICED A PLACEBO PROGRAM OF RELAXATION. ON EACH TRAINING DAY THEY UNDERWENT AMBULATORY 24 H HOLTER MONITORING. THE GROUP OF YOGA PRACTITIONERS WAS COMPARED TO A MATCHED GROUP OF HEALTHY INDIVIDUALS NOT PRACTICING ANY RELAXATION TECHNIQUES. PARAMETERS OF HEART RATE VARIABILITY (HRV) WERE DETERMINED HOURLY BY A BLINDED OBSERVER. MEAN RR INTERVAL (INTERVAL BETWEEN TWO R-WAVES OF THE ECG) WAS SIGNIFICANTLY HIGHER DURING THE TIME OF YOGA INTERVENTION COMPARED TO PLACEBO AND TO CONTROL (P < 0.001 FOR BOTH). THE INCREASE IN HRV PARAMETERS WAS SIGNIFICANTLY HIGHER DURING YOGA EXERCISE THAN DURING PLACEBO AND CONTROL ESPECIALLY FOR THE PARAMETERS ASSOCIATED WITH VAGAL TONE, I.E. MEAN STANDARD DEVIATION OF NN (NORMAL BEAT TO NORMAL BEAT OF THE ECG) INTERVALS FOR ALL 5-MIN INTERVALS (SDNNI, P < 0.001 FOR BOTH) AND ROOT MEAN SQUARE SUCCESSIVE DIFFERENCE (RMSSD, P < 0.01 FOR BOTH). IN CONCLUSION, RELAXATION BY YOGA TRAINING IS ASSOCIATED WITH A SIGNIFICANT INCREASE OF CARDIAC VAGAL MODULATION. SINCE THIS METHOD IS EASY TO APPLY WITH NO SIDE EFFECTS, IT COULD BE A SUITABLE INTERVENTION IN CARDIAC REHABILITATION PROGRAMS.	2007	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
12 1317  46 HEART RATE VARIABILITY CHANGES DURING HIGH FREQUENCY YOGA BREATHING AND BREATH AWARENESS. BACKGROUND: PRE AND POST COMPARISON AFTER ONE MINUTE OF HIGH FREQUENCY YOGA BREATHING (HFYB) SUGGESTED THAT THE HFYB MODIFIES THE AUTONOMIC STATUS BY INCREASING SYMPATHETIC MODULATION, BUT ITS EFFECT DURING THE PRACTICE WAS NOT ASSESSED. METHODS: THIRTY-EIGHT MALE VOLUNTEERS WITH GROUP AVERAGE AGE +/- S.D., 23.3 +/- 4.4 YEARS WERE EACH ASSESSED ON TWO SEPARATE DAYS IN TWO SESSIONS, (I) HFYB AND (II) BREATH AWARENESS. EACH SESSION WAS FOR 35 MINUTES, WITH 3 PERIODS, I.E., PRE (5 MINUTES), DURING HFYB OR BREATH AWARENESS (15 MINUTES) AND POST (5 MINUTES). RESULTS: THERE WAS A SIGNIFICANT DECREASE IN NN50, PNN50 AND THE MEAN RR INTERVAL DURING AND AFTER HFYB AND AFTER BREATH AWARENESS, COMPARED TO THE RESPECTIVE 'PRE' VALUES (P < 0.05) (REPEATED MEASURES ANOVA FOLLOWED BY POST-HOC ANALYSIS). THE LF POWER INCREASED AND HF POWER DECREASED DURING AND AFTER BREATH AWARENESS AND LF/HF RATIO INCREASED AFTER BREATH AWARENESS (P < 0.05). CONCLUSION: THE RESULTS SUGGEST THAT THERE WAS REDUCED PARASYMPATHETIC MODULATION DURING AND AFTER HFYB AND INCREASED SYMPATHETIC MODULATION WITH REDUCED PARASYMPATHETIC MODULATION DURING AND AFTER BREATH AWARENESS.	2011	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
13  297  49 ALTERNATE NOSTRIL BREATHING AT DIFFERENT RATES AND ITS INFLUENCE ON HEART RATE VARIABILITY IN NON PRACTITIONERS OF YOGA. INTRODUCTION: HEART RATE VARIABILITY IS A MEASURE OF MODULATION IN AUTONOMIC INPUT TO THE HEART AND IS ONE OF THE MARKERS OF AUTONOMIC FUNCTIONS. THOUGH THERE ARE MANY STUDIES ON THE LONG TERM INFLUENCE OF BREATHING ON HRV (HEART RATE VARIABILITY) THERE ARE ONLY A FEW STUDIES ON THE IMMEDIATE EFFECT OF BREATHING ESPECIALLY ALTERNATE NOSTRIL BREATHING ON HRV. THIS STUDY FOCUSES ON THE IMMEDIATE EFFECTS OF ALTERNATE NOSTRIL BREATHING AND THE INFLUENCE OF DIFFERENT BREATHING RATES ON HRV. MATERIALS AND METHODS: THE STUDY WAS DONE ON 25 SUBJECTS IN THE AGE GROUP OF 17-35 YEARS. ECG AND RESPIRATION WERE RECORDED BEFORE INTERVENTION AND IMMEDIATELY AFTER THE SUBJECTS WERE ASKED TO PERFORM ALTERNATE NOSTRIL BREATHING FOR FIVE MINUTES. RESULTS: LOW FREQUENCY (LF) WHICH IS A MARKER OF SYMPATHETIC ACTIVITY INCREASED, HIGH FREQUENCY (HF) WHICH IS A MARKER OF PARASYMPATHETIC ACTIVITY DECREASED AND THEIR RATIO LF/HF WHICH IS A MARKER OF SYMPATHO/VAGAL BALANCE INCREASED IMMEDIATELY AFTER 6 AND 12 MINUTES IN COMPARISON TO BASELINE VALUES WHEREAS THERE WAS NO SIGNIFICANT DIFFERENCE IN THE MEANS OF THESE COMPONENTS WHEN BOTH 6 AND 12 MINUTES WERE COMPARED. CONCLUSION: IMMEDIATE EFFECTS OF ALTERNATE NOSTRIL BREATHING ON HRV IN NON PRACTITIONERS OF YOGIC BREATHING ARE VERY DIFFERENT FROM THE LONG TERM INFLUENCE OF YOGIC BREATHING ON HRV WHICH SHOW A PREDOMINANT PARASYMPATHETIC INFLUENCE ON THE HEART.	2016	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
14 2731  59 YOGA OFFERS CARDIOVASCULAR PROTECTION IN EARLY POSTMENOPAUSAL WOMEN. CONTEXT: POSTMENOPAUSE, AN ESTROGEN DEFICIENT STATE COMES WITH INCREASED INCIDENCE OF CARDIOVASCULAR DISEASES (CVDS). YOGA HAS BEEN DESCRIBED AS HAVING A BENEFICIAL EFFECT ON HEART RATE VARIABILITY (HRV), A MARKER FOR CARDIAC AUTONOMIC ACTIVITY WHICH CAN ASSESS CARDIOVASCULAR RISK, IN VARIOUS POPULATIONS. AIM: THE AIM OF THE STUDY WAS TO STUDY THE EFFECT OF 3-MONTH LONG YOGA PRACTICE ON HRV IN EARLY POSTMENOPAUSAL WOMEN. SETTINGS AND DESIGN: A PROSPECTIVE LONGITUDINAL STUDY OF 67 WOMEN WITHIN 5 YEARS OF MENOPAUSE BETWEEN 45 AND 60 YEARS OF AGE ATTENDING MENOPAUSE CLINIC OF DEPARTMENT OF GYNAECOLOGY, SUCHETA KRIPLANI HOSPITAL FULFILLING INCLUSION AND EXCLUSION CRITERIA AND CONSENTING WERE ENROLLED FOR THE STUDY. SUBJECTS AND METHODS: HRV OF 37 CASES (YOGA GROUP) AND 30 CONTROLS (NON-YOGA GROUP) WAS RECORDED PRE AND 3-MONTH POSTINTERVENTION. STATISTICAL ANALYSIS USED: GRAPHPAD PRISM VERSION 5 SOFTWARE WAS USED. VALUES ARE A MEAN AND STANDARD ERROR OF MEAN. STATISTICAL SIGNIFICANCE WAS SET UP AT P < 0.05. RESULTS: IN HRV, FREQUENCY DOMAIN ANALYSIS SHOWED A SIGNIFICANT FALL IN LOW FREQUENCY (LF) IN NORMALIZED UNITS (NU) AND LF: HIGH FREQUENCY (HF) RATIO AND SIGNIFICANT RISE IN HF IN NU IN THE YOGA GROUP (DEPICTING PARASYMPATHETIC DOMINANCE) AGAINST A SIGNIFICANT RISE IN LF (NU) AND LF: HF RATIO AND SIGNIFICANT FALL IN HF (NU) IN NON-YOGA GROUP (INDICATING SYMPATHETIC DOMINANCE). TIME DOMAIN ANALYSIS SHOWED A SIGNIFICANT DECREASE IN STANDARD DEVIATION OF NN INTERVALS IN NON-YOGA GROUP AGAINST NONSIGNIFICANT CHANGES IN YOGA GROUP INDICATING DETERIORATION IN PARASYMPATHETIC ACTIVITY IN NON-YOGA GROUP. CONCLUSIONS: THREE-MONTH LONG YOGA PRACTICE IMPROVED HRV IN EARLY POSTMENOPAUSAL WOMEN SIGNIFICANTLY AND HAS THE POTENTIAL TO ATTENUATE THE CVD RISK IN POSTMENOPAUSAL WOMEN.	2018	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
15 2065  62 THE CARDIOVASCULAR VARIABILITY DURING TRANSIENT 6 DEGREES HEAD DOWN TILT AND SLOW BREATHING IN YOGA EXPERIENCED HEALTHY INDIVIDUALS. OBJECTIVE: THE INTERVENTION OF YOGA HAS BEEN SHOWN TO IMPROVE AUTONOMIC CONDITIONING IN HUMANS AND BETTER ADAPTABILITY TO ORTHOSTATIC CHALLENGES. SIMILARLY, SLOW BREATHING AT 0.1 HZ AKIN TO PRANAYAMA ALSO INCREASES BAROREFLEX SENSITIVITY (BRS). HENCE, WE INTENDED TO INVESTIGATE WHETHER YOGA PRACTITIONERS HAVE DIFFERENT AUTONOMIC RESPONSES AT REST,DURING SLOW DEEP BREATHINGAS WELL AS DURING 6 DEGREES HEAD DOWN TILT (HDT) COMPARED TO NAIVE GROUP INDIVIDUALS. AIM: THE AIM OF THE STUDY WAS TO EVALUATE THE ACUTE EFFECTS OF SLOW BREATHING ON CARDIOVASCULAR VARIABILITY DURING HDT IN YOGA PRACTITIONERS COMPARED TO YOGA-NAIVE INDIVIDUALS. SETTINGS AND DESIGN: THIS WAS A COMPARATIVE STUDY WITH REPEATED MEASURES DESIGN CONDUCTED IN AUTONOMIC FUNCTION TEST LAB OF THE DEPARTMENT OF PHYSIOLOGY, ALL INDIA INSTITUTE OF MEDICAL SCIENCES, NEW DELHI, INDIA. MATERIALS AND METHODS: TIME DOMAIN AND FREQUENCY DOMAIN PARAMETERS OF HEART RATE VARIABILITY, BLOOD PRESSURE VARIABILITY (BPV), AND BRS WERE EVALUATED DURING 6 DEGREES HDT AND SLOW BREATHING AT 0.1 HZ ON FORTY YOGA-NAIVE INDIVIDUALS AND FORTY YOGA PRACTITIONERS WITH AN AVERAGE AGE OF 31.08 +/- 7.31 YEARS AND 29.93 +/- 7.57 YEARS, RESPECTIVELY. ALL OF THE PARTICIPANTS WERE HEALTHY. STATISTICAL ANALYSIS USED: GENERAL LINEAR MIXED MODEL ANOVA WAS APPLIED WITH YOGA EXPERIENCE AS A BETWEEN-GROUP FACTOR IN REPEATED MEASURES. INDEPENDENT SAMPLE T-TEST WAS APPLIED FOR BETWEEN GROUP COMPARISON OF RESPIRATORY RATE, DEMOGRAPHIC, AND ANTHROPOMETRIC DATA. P <0.05 IS CONSIDERED STATISTICALLY SIGNIFICANT. RESULTS: BETWEEN-GROUP COMPARISON DURING HDT WITH SPONTANEOUS BREATHING HAS SHOWN A SIGNIFICANTLY LOWER HEART RATE (P = 0.004) WITH HIGHER RR INTERVAL (RRI) (P = 0.002) AND PNN50% (P = 0.019) IN YOGA PRACTITIONERS. THE SEQUENCE BRS (P < 0.0001) AND ALPHA LOW FREQUENCY (LF) OF SPECTRAL BRS (P = 0.035) WERE ALSO SIGNIFICANTLY HIGHER IN THE YOGA GROUP COMPARED TO THE NAIVE GROUP. SIMILARLY, DURING HDT WITH SLOW BREATHING, THE HEART RATE WAS LOWER (P = 0.01); WITH HIGHER RRI (P = 0.009); PNN50% (P = 0.048). STANDARD DEVIATION OF SUCCESSIVE RR INTERVAL DIFFERENCE OF SYSTOLIC BPV WAS LOWER (P = 0.024) WITH HIGHER SEQUENCE BRS (P = 0.001) AND ALPHA LF OF SPECTRAL BRS (P = 0.002) IN YOGA GROUP THAN NAIVE GROUP. CONCLUSION: THE YOGA EXPERIENCED INDIVIDUALS EXHIBIT HIGHER RESTING PARASYMPATHETIC ACTIVITY, LOWER SYSTOLIC BPV, AND HIGHER BRS THAN NAIVE TO YOGA INDIVIDUALS. IT IS INFERRED FROM THE FINDINGS THAT YOGA PRACTITIONERS WERE BETTER ADAPTED TO TRANSIENT CEPHALAD FLUID SHIFT THAT HAPPENS DURING 6 DEGREES HDT. FURTHERMORE, ACUTE SLOW BREATHING DURING 6 DEGREES HDT REDUCED THE SYSTOLIC BLOOD PRESSURE IN ALL THE PARTICIPANTS SUGGESTING THE BENEFICIAL ROLE OF SLOW BREATHING DURING EXPOSURE TO EXTREME CONDITIONS SUCH AS MICROGRAVITY WHICH MIGHT HELP IN THE PREVENTION OF ADVERSE EFFECTS OF CEPHALAD FLUID SHIFT DURING LONG-TERM WEIGHTLESSNESS AND MAINTAIN THE ASTRONAUT HEALTH. FUTURE MECHANISTIC STUDIES WITH ACTIVE YOGA INTERVENTION ARE NECESSARY TO UNDERSTAND THE ADAPTIVE MECHANISMS INVOLVING CENTRAL AND VASCULAR MODULATIONS CONTRIBUTING TO EITHER ATTENUATION OR ACCENTUATION OF THE CARDIOVAGAL BAROREFLEX DURING HDT AND SLOW BREATHING IN HEALTHY INDIVIDUALS.	2021	

16 2727  49 YOGA NIDRA RELAXATION INCREASES HEART RATE VARIABILITY AND IS UNAFFECTED BY A PRIOR BOUT OF HATHA YOGA. OBJECTIVE: THE MEASUREMENT OF HEART RATE VARIABILITY (HRV) IS OFTEN APPLIED AS AN INDEX OF AUTONOMIC NERVOUS SYSTEM (ANS) BALANCE AND, THEREFORE, MYOCARDIAL STABILITY. PREVIOUS STUDIES HAVE SUGGESTED THAT RELAXATION OR MIND-BODY EXERCISE CAN INFLUENCE ANS BALANCE POSITIVELY AS MEASURED BY HRV BUT MAY ACT VIA DIFFERENT MECHANISMS. NO STUDIES, TO THE AUTHORS' KNOWLEDGE, HAVE EXAMINED THE ACUTE RESPONSE IN HRV TO INTERVENTIONS COMBINING RELAXATION AND MIND-BODY EXERCISE. THE OBJECTIVE OF THIS STUDY WAS TO COMPARE THE ACUTE HRV RESPONSES TO YOGA NIDRA RELAXATION ALONE VERSUS YOGA NIDRA RELAXATION PRECEDED BY HATHA YOGA. DESIGN: THIS WAS A RANDOMIZED COUNTER-BALANCED TRIAL. SETTING: THE TRIAL WAS CONDUCTED IN A UNIVERSITY EXERCISE PHYSIOLOGY LABORATORY. SUBJECTS: SUBJECTS INCLUDED 20 WOMEN AND MEN (29.15+/-6.98 YEARS OF AGE, WITH A RANGE OF 18-47 YEARS). INTERVENTIONS: PARTICIPANTS COMPLETED A YOGA PLUS RELAXATION (YR) SESSION AND A RELAXATION ONLY (R) SESSION. RESULTS: THE YR CONDITION PRODUCED SIGNIFICANT CHANGES FROM BASELINE IN HEART RATE (HR; BEATS PER MINUTE [BPM], P<0.001) AND INDICES OF HRV: R-R (MS, P<0.001), PNN50 (%, P=0.009), LOW FREQUENCY (LF; %, P=0.008) AND HIGH FREQUENCY (HF; %, P=0.035). THE R CONDITION PRODUCED SIGNIFICANT CHANGES FROM BASELINE IN HEART RATE (BPM, P<0.001) AS WELL AS INDICES OF HRV: R-R (MS, P<0.001), HF (MS(2), P=0.004), LF (%, P=0.005), HF (%, P=0.008) AND LF:HF RATIO (%, P=0.008). THERE WERE NO SIGNIFICANT DIFFERENCES BETWEEN CONDITIONS AT BASELINE NOR FOR THE CHANGES FROM BASELINE FOR ANY OF THE VARIABLES. CONCLUSIONS: THESE CHANGES DEMONSTRATE A FAVORABLE SHIFT IN AUTONOMIC BALANCE TO THE PARASYMPATHETIC BRANCH OF THE ANS FOR BOTH CONDITIONS, AND THAT YOGA NIDRA RELAXATION PRODUCES FAVORABLE CHANGES IN MEASURES OF HRV WHETHER ALONE OR PRECEDED BY A BOUT OF HATHA YOGA.	2012	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
17  452  45 CHANGES IN HEART RATE VARIABILITY AFTER YOGA ARE DEPENDENT ON HEART RATE VARIABILITY AT BASELINE AND DURING YOGA: A STUDY SHOWING AUTONOMIC NORMALIZATION EFFECT IN YOGA-NAIVE AND EXPERIENCED SUBJECTS. BACKGROUND: YOGA THERAPY IS WIDELY APPLIED TO THE MAINTENANCE OF HEALTH AND TO TREATMENT OF VARIOUS ILLNESSES. PREVIOUS RESEARCHES INDICATE THE INVOLVEMENT OF AUTONOMIC CONTROL IN ITS EFFECTS, ALTHOUGH THE GENERAL AGREEMENT HAS NOT BEEN REACHED REGARDING THE ACUTE MODULATION OF AUTONOMIC FUNCTION. AIM: THE PRESENT STUDY AIMED AT REVEALING THE ACUTE EFFECT OF YOGA ON THE AUTONOMIC ACTIVITY USING HEART RATE VARIABILITY (HRV) MEASUREMENT. METHODS: TWENTY-SEVEN HEALTHY CONTROLS PARTICIPATED IN THE PRESENT STUDY. FIFTEEN OF THEM (39.5 +/- 8.5 YEARS OLD) WERE NAIVE AND 12 (45.1 +/- 7.0 YEARS OLD) WERE EXPERIENCED IN YOGA. YOGA SKILLS INCLUDED BREATH AWARENESS, TWO TYPES OF ASANA, AND TWO TYPES OF PRANAYAMA. HRV WAS MEASURED AT THE BASELINE, DURING YOGA, AND AT THE RESTING STATE AFTER YOGA. RESULTS: IN BOTH YOGA-NAIVE AND EXPERIENCED PARTICIPANTS, THE CHANGES IN LOW-FREQUENCY (LF) COMPONENT OF HRV AND ITS RATIO TO HIGH-FREQUENCY (HF) COMPONENT (LF/HF) AFTER YOGA WERE FOUND TO BE CORRELATED NEGATIVELY WITH THE BASELINE DATA. THE CHANGES IN LF AFTER YOGA WERE ALSO CORRELATED WITH LF DURING YOGA. THE CHANGES IN HF AS WELL AS THE RAW HRV DATA AFTER YOGA WERE NOT RELATED TO THE BASELINE HRV OR THE HRV DURING YOGA. CONCLUSION: THE RESULTS INDICATE THAT YOGA LEADS TO AN INCREASE IN LF WHEN LF IS LOW AND LEADS TO A DECREASE IN LF WHEN IT IS HIGH AT THE BASELINE. THIS NORMALIZATION OF LF IS DEPENDENT ON THE AUTONOMIC MODULATION DURING YOGA AND MAY UNDERLIE THE CLINICAL EFFECTIVENESS OF YOGA THERAPY BOTH IN YOGA-NAIVE AND EXPERIENCED SUBJECTS.	2020	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     
18 1318  50 HEART RATE VARIABILITY IN CHRONIC LOW BACK PAIN PATIENTS RANDOMIZED TO YOGA OR STANDARD CARE. BACKGROUND: CHRONIC PAIN CAN ALTER THE AUTONOMIC BALANCE WITH INCREASED SYMPATHETIC ACTIVITY REFLECTED IN ALTERED HEART RATE VARIABILITY (HRV). IT HAS BEEN PROPOSED THAT YOGA CAN BE USEFUL TO CORRECT THE AUTONOMIC IMBALANCE IN PATIENTS WITH CHRONIC PAIN WHO HAVE REDUCED HRV. METHODS AND DESIGNS: IN THE PRESENT RANDOMIZED CONTROLLED TRIAL 62 PATIENTS WITH CHRONIC LOW BACK PAIN ASSOCIATED WITH ALTERED ALIGNMENT OF INTERVERTEBRAL DISCS (AGED BETWEEN 20 AND 45 YEARS, 32 MALES) WERE RANDOMIZED TO 2 GROUPS. ONE GROUP RECEIVED YOGA FOR 3 MONTHS WHILE THE OTHER GROUP CARRIED OUT STANDARD MEDICAL CARE BASED ON THE PHYSICIAN'S ADVICE. THE DURATION WAS THE SAME, I.E., 3 MONTHS. THE HEART RATE VARIABILITY AND RATE OF RESPIRATION WERE ASSESSED AT BASELINE AND AT THE END OF 3 MONTHS. RESULTS: THERE WAS A SIGNIFICANT DIFFERENCE IN THE BASELINE (PRE) VALUES BETWEEN GROUPS (P = 0.008) FOR RESPIRATION RATE WHICH WAS HIGHER IN THE YOGA GROUP. THE CHANGES REPORTED BELOW ARE PRE-POST COMPARISONS WITHIN EACH GROUP. THE YOGA GROUP SHOWED A SIGNIFICANT (P < 0.05; REPEATED MEASURES ANOVA, POST-HOC ANALYSES) DECREASE IN THE LF POWER OF HRV, RATE OF RESPIRATION AND A SIGNIFICANT INCREASE IN THE HF POWER OF HRV AND IN THE PNN50. CONCLUSION: THE RESULTS SUGGEST THAT YOGA PRACTICE CAN SHIFT THE AUTONOMIC BALANCE TOWARDS VAGAL DOMINANCE IN PATIENTS WITH CHRONIC LOW BACK PAIN ASSOCIATED WITH ALTERED ALIGNMENT OF INTERVERTEBRAL DISCS. TRIAL REGISTRATION: THE STUDY IS REGISTERED WITH THE CLINICAL TRIALS REGISTRY OF INDIA ( CTRI/2012/11/003094 ) AND CAN BE ACCESSED AT.	2016	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
19  846  41 EFFECT OF YOGA ON PULSE RATE VARIABILITY MEASURED FROM A VENOUS PRESSURE WAVEFORM. THE BENEFITS OF YOGA HAVE BEEN STUDIED IN DIFFERENT FIELDS, FROM CHRONIC HEALTH CONDITIONS TO MENTAL DISORDERS, SHOWING THAT IT CAN HELP TO IMPROVE THE OVERALL HEALTH. IN PARTICULAR, IT HAS BEEN PROVEN THAT YOGA ALSO IMPROVES THE AUTONOMIC FUNCTION. HEART RATE VARIABILITY (HRV) AT REST IS COMMONLY USED AS A NON-INVASIVE MEASURE OF AUTONOMIC REGULATION OF HEART RATE. ALTERNATIVELY, PULSE RATE VARIABILITY (PRV) HAS BEEN PROPOSED AS A SURROGATE OF HRV. VOLUMETRIX HAS DEVELOPED A NOVEL TECHNOLOGY THAT CAPTURES VENOUS WAVEFORMS VIA SENSORS ON THE VOLAR ASPECT OF THE WRIST, CALLED NIVABAND. THIS STUDY AIMS TO ASSESS THE EFFECT OF YOGA IN THE AUTONOMIC NERVOUS SYSTEM BY ANALYZING THE PRV OBTAINED FROM THE NIVA SIGNAL. TEMPORAL (STATISTICS OF THE NORMAL-TO-NORMAL INTERVALS), SPECTRAL (POWER IN LOW AND HIGH FREQUENCY BANDS) AND NONLINEAR (LAGGED POINCARE PLOT ANALYSIS) PARAMETERS ARE ANALYZED BEFORE AND AFTER A YOGA SESSION IN 20 HEALTHY VOLUNTEERS. THE PRV ANALYSIS SHOWS AN INCREASE IN PARAMETERS RELATED TO PARASYMPATHETIC ACTIVITY AND OVERALL VARIABILITY, AND A DECREASE IN PARAMETERS RELATED TO SYMPATHETIC ACTIVITY AND MEAN HEART RATE. THESE RESULTS SUPPORT THE BENEFICIAL EFFECT OF YOGA IN AUTONOMIC NERVOUS SYSTEM, INCREASING THE PARASYMPATHETIC ACTIVITY.	2019	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
20 1359  56 IMMEDIATE EFFECTS OF OM CHANTING ON HEART RATE VARIABILITY MEASURES COMPARED BETWEEN EXPERIENCED AND INEXPERIENCED YOGA PRACTITIONERS. BACKGROUND: CHANTING "OM" IS A FORM OF MEDITATION THAT HAS NUMEROUS HEALTH BENEFITS. HOWEVER, THE NEUROPHYSIOLOGICAL MECHANISMS UNDERPINNING ITS EFFECT ARE SURPRISINGLY SCARCE. THE PRESENT STUDY AIMED TO INVESTIGATE THE EFFECT OF OM CHANTING ON AUTONOMIC MODULATION, USING HEART RATE VARIABILITY (HRV), ON EXPERIENCED YOGA PRACTITIONERS AND YOGA NAIVE PERSONS. METHODS: THIS PROSPECTIVE STUDY INCLUDED 19 YOGA PRACTITIONERS (9 FEMALES AND 10 MALES; GROUP MEAN AGE +/- STANDARD DEVIATION [SD]; 25.9 +/- 3.2 YEARS) AND 17 YOGA NAIVE PERSONS (8 FEMALES AND 9 MALES; GROUP MEAN AGE +/- SD; 24.8 +/- 3.6 YEARS) OF BOTH SEXES AND SIMILAR AGE RANGE. BOTH THE GROUPS WERE ASSESSED FOR HRV INDICES (TIME AND FREQUENCY DOMAIN MEASURES) BEFORE AND AFTER LOUD OM CHANTING FOR 5 MIN. RESULTS: BASELINE COMPARISON USING MANN-WHITNEY U TEST BETWEEN GROUPS SHOWED YOGA PRACTITIONERS HAD SIGNIFICANTLY INCREASED HIGH FREQUENCY (HF) POWER (P < 0.029) THAN NONYOGA PRACTITIONERS, SIGNIFYING A STATE OF TRANQUILITY BEFORE THE CHANTING OF OM. AFTER 5 MIN OF LOUD CHANTING OF OM, A COMPARISON BETWEEN GROUPS ASSESSED USING WILCOXON SIGNED RANKS TEST REVEALED: HF POWER, A COMPONENT OF THE PARASYMPATHETIC NERVOUS SYSTEM, WAS FURTHER AMPLIFIED WITH A SIGNIFICANTLY INCREASE (P < 0.001) IN THE YOGA PRACTITIONERS GROUP COMPARED TO NONYOGA PRACTITIONERS. FURTHERMORE, THIS INCREASE IN HF POWER WAS POSITIVELY CORRELATED WITH THE YEARS OF EXPERIENCE IN YOGA. CONCLUSION: THE PRESENT STUDY SHOWED THAT A BRIEF CHANTING OF OM (5 MIN) MIGHT ENHANCE PARASYMPATHETIC NERVOUS SYSTEM ACTIVITY, PROMOTE RELAXATION, AND PROVIDE CALMNESS. FURTHER, THIS EXPERIENCE MAY BE ACHIEVED EFFECTIVELY IN INDIVIDUALS EXPERIENCED IN YOGA THAN NONYOGA PRACTITIONERS.	2022