1 1441 121 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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
2  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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
3 1027  35 EFFECTS OF YOGA BREATHING PRACTICE ON HEART RATE VARIABILITY IN HEALTHY ADOLESCENTS: A RANDOMIZED CONTROLLED TRIAL. BACKGROUND: THIS STUDY WAS CONDUCTED AMONG HEALTHY ADOLESCENTS TO ASSESS THE EFFECTS OF A YOGA BREATHING PRACTICE (BHRAMARI PRANAYAMA, BHR.P) TOWARDS CARDIAC AUTONOMIC FUNCTION USING HEART RATE VARIABILITY (HRV) PARAMETERS. METHODS: OF THE 730 ELIGIBLE SUBJECTS SCREENED, 520 HEALTHY ADOLESCENTS WHO MET THE INCLUSION AND EXCLUSION CRITERIA WERE RANDOMLY ASSIGNED TO EITHER YOGA BREATHING GROUP (N=260) OR CONTROL GROUP (N=260). THE YOGA BREATHING GROUP PRACTICED BHR.P. FIVE DAYS A WEEK FOR A DURATION OF SIX MONTHS WHILE THE CONTROL GROUP CONTINUED WITH THEIR DAILY ROUTINE WITHOUT ANY INTERVENTION. OUTCOME MEASURES WERE TIME AND FREQUENCY DOMAIN OF HRV IN BOTH GROUPS WHICH WERE ASSESSED BEFORE AND AFTER THE INTERVENTION USING LEAD II ECG. LINEAR MODELS WERE USED IN THE ANALYSIS OF SHORT TERM HRV. RESULTS: AFTER 6 MONTHS OF YOGA BREATHING, THE TIME DOMAIN PARAMETERS OF SHORT TERM HRV SHOWED SIGNIFICANT (P<0.05) IMPROVEMENT TOWARDS THE PARASYMPATHETIC DOMAIN. FREQUENCY DOMAIN PARAMETERS ALSO SHOWED THE SAME DIRECTION OF CHANGES. IN CONTRAST, CONTROL GROUP SUBJECTS SHOWED A TREND TOWARDS A SYMPATHETIC DOMAIN. CONCLUSION: THE PRESENT STUDY SHOWED A POSITIVE SHIFT IN CARDIAC AUTONOMIC MODULATION TOWARDS PARASYMPATHETIC PREDOMINANCE AFTER 6 MONTHS OF YOGA BREATHING PRACTICE AMONG APPARENTLY HEALTHY ADOLESCENTS.	2020	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
4 1530  43 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	
                                                                                                                                                                                                                                                                                                                                                                  
5  297  44 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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
6 2727  46 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	
                                                                                                                                                                                                                                                                                                                                                                                               
7 1578  48 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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          
8  873  43 EFFECT OF YOGA THERAPY ON HEART RATE, BLOOD PRESSURE AND CARDIAC AUTONOMIC FUNCTION IN HEART FAILURE. BACKGROUND AND OBJECTIVE: IT IS WELL KNOWN THAT A HALL MARK OF HEART FAILURE IS ADVERSE CHANGES IN AUTONOMIC FUNCTION. ELEVATED BLOOD PRESSURE IS A POWERFUL PREDICTOR OF CONGESTIVE HEART FAILURE AND OTHER CARDIOVASCULAR DISEASE (CVD) OUTCOMES. IN THIS STUDY, WE PLANNED TO EXAMINE THE EFFECTS OF A 12 WEEK YOGA THERAPY ON BLOOD PRESSURE, HEART RATE, HEART RATE VARIABILITY, AND RATE PRESSURE PRODUCT (RPP). METHODS: OUT OF 130 HEART FAILURE PATIENTS RECRUITED FOR THE STUDY, 65 PATIENTS WERE RANDOMLY SELECTED TO RECEIVE 12 WEEK YOGA THERAPY ALONG WITH STANDARD MEDICAL THERAPY (YOGA GROUP). OTHER PATIENTS (N=65) RECEIVED ONLY STANDARD MEDICAL THERAPY (CONTROL GROUP). HEART RATE, BLOOD PRESSURE, CARDIAC AUTONOMIC FUNCTION (BY SHORT-TERM HEART-RATE VARIABILITY ANALYSIS) AND MYOCARDIAL OXYGEN CONSUMPTION (BY RPP) WERE ASSESSED BEFORE AND AFTER 12 WEEKS. IN THE YOGA GROUP, 44 PATIENTS AND IN THE CONTROL GROUP, 48 PATIENTS COMPLETED THE STUDY. RESULTS: THERE WAS A SIGNIFICANT DECREASE IN HEART RATE, BLOOD PRESSURE AND RPP IN YOGA GROUP COMPARED TO CONTROL GROUP. ALSO, LFNU AND LF-HF RATIO DECREASED SIGNIFICANTLY AND HFNU INCREASED SIGNIFICANTLY IN YOGA GROUP COMPARED TO CONTROL GROUP. CONCLUSION: TWELVE-WEEK YOGA THERAPY SIGNIFICANTLY IMPROVED THE PARASYMPATHETIC ACTIVITY AND DECREASED THE SYMPATHETIC ACTIVITY IN HEART FAILURE PATIENTS (NYHA I&II).	2014	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
9 2775  36 YOGA RESPIRATORY TRAINING IMPROVES RESPIRATORY FUNCTION AND CARDIAC SYMPATHOVAGAL BALANCE IN ELDERLY SUBJECTS: A RANDOMISED CONTROLLED TRIAL. OBJECTIVES: SINCE AGEING IS ASSOCIATED WITH A DECLINE IN PULMONARY FUNCTION, HEART RATE VARIABILITY AND SPONTANEOUS BAROREFLEX, AND RECENT STUDIES SUGGEST THAT YOGA RESPIRATORY EXERCISES MAY IMPROVE RESPIRATORY AND CARDIOVASCULAR FUNCTION, WE HYPOTHESISED THAT YOGA RESPIRATORY TRAINING MAY IMPROVE RESPIRATORY FUNCTION AND CARDIAC AUTONOMIC MODULATION IN HEALTHY ELDERLY SUBJECTS. DESIGN: 76 HEALTHY ELDERLY SUBJECTS WERE ENROLLED IN A RANDOMISED CONTROL TRIAL IN BRAZIL AND 29 COMPLETED THE STUDY (AGE 68 +/- 6 YEARS, 34% MALES, BODY MASS INDEX 25 +/- 3 KG/M(2)). SUBJECTS WERE RANDOMISED INTO A 4-MONTH TRAINING PROGRAM (2 CLASSES/WEEK PLUS HOME EXERCISES) OF EITHER STRETCHING (CONTROL, N=14) OR RESPIRATORY EXERCISES (YOGA, N=15). YOGA RESPIRATORY EXERCISES (BHASTRIKA) CONSISTED OF RAPID FORCED EXPIRATIONS FOLLOWED BY INSPIRATION THROUGH THE RIGHT NOSTRIL, INSPIRATORY APNOEA WITH GENERATION OF INTRATHORACIC NEGATIVE PRESSURE, AND EXPIRATION THROUGH THE LEFT NOSTRIL. PULMONARY FUNCTION, MAXIMUM EXPIRATORY AND INSPIRATORY PRESSURES (PE(MAX) AND PI(MAX), RESPECTIVELY), HEART RATE VARIABILITY AND BLOOD PRESSURE VARIABILITY FOR SPONTANEOUS BAROREFLEX DETERMINATION WERE DETERMINED AT BASELINE AND AFTER 4 MONTHS. RESULTS: SUBJECTS IN BOTH GROUPS HAD SIMILAR DEMOGRAPHIC PARAMETERS. PHYSIOLOGICAL VARIABLES DID NOT CHANGE AFTER 4 MONTHS IN THE CONTROL GROUP. HOWEVER, IN THE YOGA GROUP, THERE WERE SIGNIFICANT INCREASES IN PE(MAX) (34%, P<0.0001) AND PI(MAX) (26%, P<0.0001) AND A SIGNIFICANT DECREASE IN THE LOW FREQUENCY COMPONENT (A MARKER OF CARDIAC SYMPATHETIC MODULATION) AND LOW FREQUENCY/HIGH FREQUENCY RATIO (MARKER OF SYMPATHOVAGAL BALANCE) OF HEART RATE VARIABILITY (40%, P<0.001). SPONTANEOUS BAROREFLEX DID NOT CHANGE, AND QUALITY OF LIFE ONLY MARGINALLY INCREASED IN THE YOGA GROUP. CONCLUSION: RESPIRATORY YOGA TRAINING MAY BE BENEFICIAL FOR THE ELDERLY HEALTHY POPULATION BY IMPROVING RESPIRATORY FUNCTION AND SYMPATHOVAGAL BALANCE. TRIAL REGISTRATION CINICALTRIALS.GOV IDENTIFIER: NCT00969345; TRIAL REGISTRY NAME: EFFECTS OF RESPIRATORY YOGA TRAINING (BHASTRIKA) ON HEART RATE VARIABILITY AND BAROREFLEX, AND QUALITY OF LIFE OF HEALTHY ELDERLY SUBJECTS.	2011	

10 2817  39 YOGA TRAINING IMPROVES QUALITY OF LIFE IN WOMEN WITH ASTHMA. OBJECTIVES: INDIVIDUALS WITH ASTHMA FREQUENTLY SUFFER WITH A DECREASE IN QUALITY OF LIFE. YOGA HAS BEEN SHOWN TO IMPROVE AUTONOMIC FUNCTION IN THE HEALTHY POPULATION AND HAS BEEN USED AS AN ALTERNATIVE THERAPY TO HELP IMPROVE SYMPTOMS ASSOCIATED WITH VARIOUS DISEASES. PURPOSE: THE PURPOSE OF THIS STUDY WAS TO ASSESS WHETHER 10 WEEKS OF YOGA TRAINING CAN IMPROVE QUALITY OF LIFE AND HEART RATE VARIABILITY (HRV) IN PATIENTS WITH ASTHMA. DESIGN: NINETEEN (19) FEMALES WERE RANDOMLY ASSIGNED TO A YOGA GROUP OR A CONTROL GROUP FOR A 10-WEEK INTERVENTION WHILE STILL FOLLOWING GUIDELINES ESTABLISHED BY THEIR PHYSICIAN. ALL SUBJECTS ANSWERED THE ST. GEORGE'S RESPIRATORY QUESTIONNAIRE (SGRQ) TO ASSESS QUALITY OF LIFE AND PERFORMED AN ISOMETRIC HANDGRIP EXERCISE TEST TO ASSESS HRV. RESULTS: BASED ON THE SGRQ, SIGNIFICANT IMPROVEMENTS (45%, P < 0.05) IN QUALITY OF LIFE WERE OBSERVED WITH THE YOGA TRAINING, WHILE NO CHANGES WERE FOUND IN THE CONTROL GROUP. RESTING HEMODYNAMIC MEASURES IMPROVED SIGNIFICANTLY IN THE YOGA GROUP COMPARED TO THE CONTROL GROUP (P < 0.05). THE YOGA GROUP DECREASED PARASYMPATHETIC MODULATION (HFNU [NORMALIZED UNITS]) PRE- TO POSTINTERVENTION (0.45 +/- 0.60 TO 0.35 +/- 0.06 NU, P<0.05, RESPECTIVELY) IN RESPONSE TO THE ISOMETRIC FOREARM EXERCISE (IFE), WHEREAS THE CONTROL GROUP DID NOT CHANGE. ADDITIONALLY, THE YOGA GROUP INCREASED SYMPATHETIC (LFNU) (PRE 0.47 +/- 0.07 TO POST 0.60 +/- 0.07 NU, P < 0.05) AND SYMPATHOVAGAL MODULATION (LOGLF/HF) (PRE 4.61 +/- 0.39 TO POST 5.31 +/- 0.44, P < 0.05, RESPECTIVELY) DURING IFE WITH NO CHANGE IN THE CONTROL GROUP. CONCLUSIONS: YOGA TRAINING IMPROVED QUALITY OF LIFE IN WOMEN WITH MILD-TO-MODERATE ASTHMA AND RESULTED IN DECREASED PARASYMPATHETIC AND INCREASED SYMPATHETIC MODULATION IN RESPONSE TO AN IFE.	2012	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
11 1318  49 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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
12  243  37 A YOGA & EXERCISE RANDOMIZED CONTROLLED TRIAL FOR VASOMOTOR SYMPTOMS: EFFECTS ON HEART RATE VARIABILITY. OBJECTIVES: HEART RATE VARIABILITY (HRV) REFLECTS THE INTEGRATION OF THE PARASYMPATHETIC NERVOUS SYSTEM WITH THE REST OF THE BODY. STUDIES ON THE EFFECTS OF YOGA AND EXERCISE ON HRV HAVE BEEN MIXED BUT SUGGEST THAT EXERCISE INCREASES HRV. WE CONDUCTED A SECONDARY ANALYSIS OF THE EFFECT OF YOGA AND EXERCISE ON HRV BASED ON A RANDOMIZED CLINICAL TRIAL OF TREATMENTS FOR VASOMOTOR SYMPTOMS IN PERI/POST-MENOPAUSAL WOMEN. DESIGN: RANDOMIZED CLINICAL TRIAL OF BEHAVIORAL INTERVENTIONS IN WOMEN WITH VASOMOTOR SYMPTOMS (N=335), 40-62 YEARS OLD FROM THREE CLINICAL STUDY SITES. INTERVENTIONS: 12-WEEKS OF A YOGA PROGRAM, DESIGNED SPECIFICALLY FOR MID-LIFE WOMEN, OR A SUPERVISED AEROBIC EXERCISE-TRAINING PROGRAM WITH SPECIFIC INTENSITY AND ENERGY EXPENDITURE GOALS, COMPARED TO A USUAL ACTIVITY GROUP. MAIN OUTCOME MEASURES: TIME AND FREQUENCY DOMAIN HRV MEASURED AT BASELINE AND AT 12 WEEKS FOR 15MIN USING HOLTER MONITORS. RESULTS: WOMEN HAD A MEDIAN OF 7.6 VASOMOTOR SYMPTOMS PER 24H. TIME AND FREQUENCY DOMAIN HRV MEASURES DID NOT CHANGE SIGNIFICANTLY IN EITHER OF THE INTERVENTION GROUPS COMPARED TO THE CHANGE IN THE USUAL ACTIVITY GROUP. HRV RESULTS DID NOT DIFFER WHEN THE ANALYSES WERE RESTRICTED TO POST-MENOPAUSAL WOMEN. CONCLUSIONS: ALTHOUGH YOGA AND EXERCISE HAVE BEEN SHOWN TO INCREASE PARASYMPATHETIC-MEDIATED HRV IN OTHER POPULATIONS, NEITHER INTERVENTION INCREASED HRV IN MIDDLE-AGED WOMEN WITH VASOMOTOR SYMPTOMS. MIXED RESULTS IN PREVIOUS RESEARCH MAY BE DUE TO SAMPLE DIFFERENCES. YOGA AND EXERCISE LIKELY IMPROVE SHORT-TERM HEALTH IN MIDDLE-AGED WOMEN THROUGH MECHANISMS OTHER THAN HRV.	2016	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
13 2863  34 YOGA-BASED GUIDED RELAXATION REDUCES SYMPATHETIC ACTIVITY JUDGED FROM BASELINE LEVELS. 35 MALE VOLUNTEERS WHOSE AGES RANGED FROM 20 TO 46 YEARS WERE STUDIED IN TWO SESSIONS OF YOGA-BASED GUIDED RELAXATION AND SUPINE REST. ASSESSMENTS OF AUTONOMIC VARIABLES WERE MADE FOR 15 SUBJECTS, BEFORE, DURING, AND AFTER THE PRACTICES, WHEREAS OXYGEN CONSUMPTION AND BREATH VOLUME WERE RECORDED FOR 25 SUBJECTS BEFORE AND AFTER BOTH TYPES OF RELAXATION. A SIGNIFICANT DECREASE IN OXYGEN CONSUMPTION AND INCREASE IN BREATH VOLUME WERE RECORDED AFTER GUIDED RELAXATION (PAIRED T TEST). THERE WERE COMPARABLE REDUCTIONS IN HEART RATE AND SKIN CONDUCTANCE DURING BOTH TYPES OF RELAXATION. DURING GUIDED RELAXATION THE POWER OF THE LOW FREQUENCY COMPONENT OF THE HEART-RATE VARIABILITY SPECTRUM REDUCED, WHEREAS THE POWER OF THE HIGH FREQUENCY COMPONENT INCREASED, SUGGESTING REDUCED SYMPATHETIC ACTIVITY. ALSO, SUBJECTS WITH A BASELINE RATIO OF LF/HF > 0.5 SHOWED A SIGNIFICANT DECREASE IN THE RATIO AFTER GUIDED RELAXATION, WHILE SUBJECTS WITH A RATIO < OR = 0.5 AT BASELINE SHOWED NO SUCH CHANGE. THE RESULTS SUGGEST THAT SYMPATHETIC ACTIVITY DECREASED AFTER GUIDED RELAXATION BASED ON YOGA, DEPENDING ON THE BASELINE LEVELS.	2002	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
14 1258  32 FIFTEEN MINUTES OF CHAIR-BASED YOGA POSTURES OR GUIDED MEDITATION PERFORMED IN THE OFFICE CAN ELICIT A RELAXATION RESPONSE. THIS STUDY COMPARED ACUTE (15 MIN) YOGA POSTURE AND GUIDED MEDITATION PRACTICE, PERFORMED SEATED IN A TYPICAL OFFICE WORKSPACE, ON PHYSIOLOGICAL AND PSYCHOLOGICAL MARKERS OF STRESS. TWENTY PARTICIPANTS (39.6 +/- 9.5 YR) COMPLETED THREE CONDITIONS: YOGA, MEDITATION, AND CONTROL (I.E., USUAL WORK) SEPARATED BY >/=24 HRS. YOGA AND MEDITATION SIGNIFICANTLY REDUCED PERCEIVED STRESS VERSUS CONTROL, AND THIS EFFECT WAS MAINTAINED POSTINTERVENTION. YOGA INCREASED HEART RATE WHILE MEDITATION REDUCED HEART RATE VERSUS CONTROL (P < 0.05). RESPIRATION RATE WAS REDUCED DURING YOGA AND MEDITATION VERSUS CONTROL (P < 0.05). DOMAINS OF HEART RATE VARIABILITY (E.G., SDNN AND TOTAL POWER) WERE SIGNIFICANTLY REDUCED DURING CONTROL VERSUS YOGA AND MEDITATION. SYSTOLIC AND DIASTOLIC BLOOD PRESSURE WERE REDUCED SECONDARY TO MEDITATION VERSUS CONTROL ONLY (P < 0.05). PHYSIOLOGICAL ADAPTATIONS GENERALLY REGRESSED TOWARD BASELINE POSTINTERVENTION. IN CONCLUSION, YOGA POSTURES OR MEDITATION PERFORMED IN THE OFFICE CAN ACUTELY IMPROVE SEVERAL PHYSIOLOGICAL AND PSYCHOLOGICAL MARKERS OF STRESS. THESE EFFECTS MAY BE AT LEAST PARTIALLY MEDIATED BY REDUCED RESPIRATION RATE.	2012	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
15  715  34 EFFECT OF INTEGRATED YOGA ON STRESS AND HEART RATE VARIABILITY IN PREGNANT WOMEN. OBJECTIVE: TO STUDY THE EFFECT OF INTEGRATED YOGA PRACTICE AND GUIDED YOGIC RELAXATION ON BOTH PERCEIVED STRESS AND MEASURED AUTONOMIC RESPONSE IN HEALTHY PREGNANT WOMEN. METHOD: THE 122 HEALTHY WOMEN RECRUITED BETWEEN THE 18TH AND 20TH WEEK OF PREGNANCY AT PRENATAL CLINICS IN BANGALORE, INDIA, WERE RANDOMIZED TO PRACTICING YOGA AND DEEP RELAXATION OR STANDARD PRENATAL EXERCISES 1-HOUR DAILY. THE RESULTS FOR THE 45 PARTICIPANTS PER GROUP WHO COMPLETED THE STUDY WERE EVALUATED BY REPEATED MEASURES ANALYSIS OF VARIANCE. RESULTS: PERCEIVED STRESS DECREASED BY 31.57% IN THE YOGA GROUP AND INCREASED BY 6.60% IN THE CONTROL GROUP (P=0.001). DURING A GUIDED RELAXATION PERIOD IN THE YOGA GROUP, COMPARED WITH VALUES OBTAINED BEFORE A PRACTICE SESSION, THE HIGH-FREQUENCY BAND OF THE HEART RATE VARIABILITY SPECTRUM (PARASYMPATHETIC) INCREASED BY 64% IN THE 20TH WEEK AND BY 150% IN THE 36TH WEEK, AND BOTH THE LOW-FREQUENCY BAND (SYMPATHETIC), AND THE LOW-FREQUENCY TO HIGH-FREQUENCY RATIO WERE CONCOMITANTLY REDUCED (P<0.001 BETWEEN THE 2 GROUPS). MOREOVER, THE LOW-FREQUENCY BAND REMAINED DECREASED AFTER DEEP RELAXATION IN THE 36TH WEEK IN THE YOGA GROUP. CONCLUSION: YOGA REDUCES PERCEIVED STRESS AND IMPROVES ADAPTIVE AUTONOMIC RESPONSE TO STRESS IN HEALTHY PREGNANT WOMEN.	2009	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
16 1988  37 SPECTRAL PARAMETERS OF HRV IN YOGA PRACTITIONERS, ATHLETES AND SEDENTARY MALES. PHYSICAL INACTIVITY IS AN IMPORTANT RISK FACTOR FOR CARDIOVASCULAR MORTALITY AND MORBIDITY. EXERCISE IS CONSIDERED AN ACCEPTABLE METHOD FOR IMPROVING AND MAINTAINING PHYSICAL AND EMOTIONAL HEALTH. ALTHOUGH YOGA IS HISTORICALLY A SPIRITUAL DISCIPLINE, A GROWING BODY OF EVIDENCE SUPPORTS THE BELIEF THAT YOGA BENEFITS PHYSICAL AND MENTAL HEALTH. THE OBJECTIVE OF THIS STUDY WAS TO EVALUATE HEART RATE VARIABILITY WHICH REFLECTS AUTONOMIC CONTROL OF HEART AMONG YOGA PRACTITIONERS, ATHLETES AND INDIVIDUALS WITH SEDENTARY LIFESTYLE. THE STUDY WAS CARRIED OUT IN THE DEPARTMENTS OF PHYSIOLOGY AT MAMC AGROHA, HISAR AND PT. BD SHARMA PGIMS ROHTAK, HARYANA. THE STUDY GROUP COMPRISED OF 1200 HEALTHY MALE VOLUNTEERS OF 16 TO 55 YEARS OF AGE. THE STUDY GROUP WAS DIVIDED INTO FOUR AGE GROUPS: GROUP A OF AGE 16 TO 25 YEARS; GROUP B OF AGE 26 TO 35 YEARS; GROUP C OF AGE 36 TO 45 YEARS AND GROUP D OF AGE 46 TO 55 YEARS. ALL AGE GROUPS WERE FURTHER DIVIDED INTO THREE CATEGORIES I.E ATHLETE (RUNNER), YOGA (YOGA PRACTITIONERS) AND SEDENTARY IN WHICH INDIVIDUALS WITH SEDENTARY LIFE STYLE WERE INCLUDED. THE BASAL RECORDING OF ECG IN LEAD II WAS DONE FOR 5 MINUTES. THE POLYRITE-D ECG DATA WAS USED FOR ANALYSIS OF HEART RATE VARIABILITY BY FREQUENCY DOMAIN METHOD. TWO SPECTRAL COMPONENTS WERE RECORDED NAMELY HIGH FREQUENCY (HF) COMPONENT (0.15-0.4 HZ), AN INDICATOR OF VAGAL EFFERENT ACTIVITY AND LOW FREQUENCY (LF) COMPONENT (0.04-.15 HZ), REPLICATOR OF COMPOSITE SYMPATHO-VAGAL INTERPLAY. HF COMPONENT IN NORMALIZED UNIT WAS FOUND SIGNIFICANTLY HIGH IN AGE GROUP B AND C IN YOGA PRACTITIONERS AND ATHLETES AS COMPARED TO SEDENTARY INDIVIDUALS AND IN AGE GROUP D SIGNIFICANTLY HIGH IN YOGA PRACTITIONERS AS COMPARED TO ATHLETES AND SEDENTARY INDIVIDUALS. SIGNIFICANTLY DECREASED LF/HF RATIO WAS FOUND IN AGE GROUP B AND C IN YOGA AND ATHLETE SUBJECTS AS COMPARED TO SEDENTARY INDIVIDUALS AND IN AGE GROUP D IN YOGA PRACTITIONERS AS COMPARED TO ATHLETES AND SEDENTARY INDIVIDUALS. THIS INDICATES THAT PARASYMPATHETIC ACTIVITY IS SUBSTANTIALLY GREATER IN YOGA PRACTITIONERS.	2015	
                                                                                                                                                                           
17  890  44 EFFECT OF YOGA-BASED CARDIAC REHABILITATION ON HEART RATE VARIABILITY: RANDOMIZED CONTROLLED TRIAL IN PATIENTS POST-MI. AUTONOMIC DYSFUNCTION IS AN INDEPENDENT PREDICTOR OF CARDIOVASCULAR AND ALL-CAUSE MORTALITY AFTER MYOCARDIAL INFARCTION (MI). WE TESTED THE EFFECTS OF A 12-WEEK YOGA-BASED CARDIAC REHABILITATION PROGRAM ON HEART RATE VARIABILITY (HRV) IN 80 PATIENTS POST-MI. THIS RANDOMIZED CONTROLLED TRIAL WITH TWO PARALLEL GROUPS WAS CARRIED OUT IN A TERTIARY CARE INSTITUTION IN INDIA. THE YOGA GROUP RECEIVED 13 HOSPITAL-BASED STRUCTURED YOGA SESSIONS AS AN ADJUNCT TO STANDARD CARE. CONTROL GROUP PARTICIPANTS RECEIVED ENHANCED STANDARD CARE INVOLVING THREE BRIEF EDUCATIONAL SESSIONS WITH A LEAFLET ON THE IMPORTANCE OF DIET AND PHYSICAL ACTIVITY. HRV WAS MEASURED IN ALL PARTICIPANTS WITH LEAD II ELECTROCARDIOGRAM (ECG) SIGNALS. ONE YOGA GROUP PATIENT'S DATA WERE EXCLUDED DUE TO ECG ABNORMALITIES. BASELINE MEASUREMENT WAS DONE 3 WEEKS POST-MI, AND POSTINTERVENTION ASSESSMENT TOOK PLACE AT THE 13TH WEEK. HRV FREQUENCY AND TIME DOMAIN INDICES WERE ANALYZED. THERE WERE NO SIGNIFICANT BETWEEN-GROUP DIFFERENCES IN THE HRV TIME DOMAIN INDICES. FREQUENCY DOMAIN INDICES SHOWED SIGNIFICANT BETWEEN-GROUP DIFFERENCES IN HF POWER (ABSOLUTE) (YOGA VS. CONTROL: 114.42 [-794.80-7,993.78] VS. -38.14 [-4,843.50-1,617.87], P = 0.005) AND TOTAL POWER (NU) (YOGA VS. CONTROL: 44.96 [21.94] VS. -19.55 [15.42], P = 0.01) WITH HIGHER HF POWER AND TOTAL POWER (NU) IN THE YOGA GROUP. IT SHOULD BE NOTED THAT THESE RESULTS CANNOT BE GENERALIZED TO HIGH RISK PATIENTS. RESPIRATORY FREQUENCY CONTROL TO CHECK FOR INFLUENCE OF RESPIRATORY RATE ON RR INTERVAL WAS NOT EVALUATED. THIS SHORT-TERM YOGA-BASED CARDIAC REHABILITATION PROGRAM HAD ADDITIVE EFFECTS IN SHIFTING SYMPATHOVAGAL BALANCE TOWARD PARASYMPATHETIC PREDOMINANCE WHILE INCREASING OVERALL HRV IN OPTIMALLY MEDICATED POST-MI PATIENTS.	2019	
                                                                                                                                                                                                                                                                                                                                                                                                                                           
18  448  44 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	
                                                                                                                        
19 1062  45 EFFECTS OF YOGA ON HEART RATE VARIABILITY AND DEPRESSIVE SYMPTOMS IN WOMEN: A RANDOMIZED CONTROLLED TRIAL. OBJECTIVES: THE PURPOSE OF THE STUDY WAS TO INVESTIGATE THE EFFECTS OF A 12-WEEK YOGA PROGRAM ON HEART RATE VARIABILITY (HRV) AND DEPRESSIVE SYMPTOMS IN DEPRESSED WOMEN. METHODS: THIS WAS A RANDOMIZED CONTROLLED TRIAL. TWENTY-SIX SEDENTARY WOMEN SCORING >/=14 ON THE BECK DEPRESSION INVENTORY-II WERE RANDOMIZED TO EITHER THE YOGA OR THE CONTROL GROUP. THE YOGA GROUP COMPLETED A 12-WEEK YOGA PROGRAM, WHICH TOOK PLACE TWICE A WEEK FOR 60 MIN PER SESSION AND CONSISTED OF BREATHING EXERCISES, YOGA POSE PRACTICE, AND SUPINE MEDITATION/RELAXATION. THE CONTROL GROUP WAS INSTRUCTED NOT TO ENGAGE IN ANY YOGA PRACTICE AND TO MAINTAIN THEIR USUAL LEVEL OF PHYSICAL ACTIVITY DURING THE COURSE OF THE STUDY. PARTICIPANTS' HRV, DEPRESSIVE SYMPTOMS, AND PERCEIVED STRESS WERE ASSESSED AT BASELINE AND POST-TEST. RESULTS: THE YOGA GROUP HAD A SIGNIFICANT INCREASE IN HIGH-FREQUENCY HRV AND DECREASES IN LOW-FREQUENCY HRV AND LOW FREQUENCY/HIGH FREQUENCY RATIO AFTER THE INTERVENTION. THE YOGA GROUP ALSO REPORTED SIGNIFICANTLY REDUCED DEPRESSIVE SYMPTOMS AND PERCEIVED STRESS. NO CHANGE WAS FOUND IN THE CONTROL GROUP. CONCLUSIONS: A 12-WEEK YOGA PROGRAM WAS EFFECTIVE IN INCREASING PARASYMPATHETIC TONE AND REDUCING DEPRESSIVE SYMPTOMS AND PERCEIVED STRESS IN WOMEN WITH ELEVATED DEPRESSIVE SYMPTOMS. REGULAR YOGA PRACTICE MAY BE RECOMMENDED FOR WOMEN TO COPE WITH THEIR DEPRESSIVE SYMPTOMS AND STRESS AND TO IMPROVE THEIR HRV.	2017	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
20 1558  40 LONG-TERM EFFECTS OF HATHA YOGA ON HEART RATE VARIABILITY IN HEALTHY PRACTITIONERS: POTENTIAL BENEFITS FOR CARDIOVASCULAR RISK REDUCTION. HATHA YOGA IS COMMONLY PRACTICED IN WESTERN COUNTRIES AND IS CLAIMED TO REDUCE RISK OF CARDIOVASCULAR DISEASE. THE PURPOSE OF THIS STUDY WAS TO EVALUATE AND COMPARE TIME-DOMAIN AND FREQUENCY-DOMAIN METRICS OF HEART RATE VARIABILITY (HRV) IN HATHA YOGA PRACTITIONERS AND HEALTHY CONTROLS. THIS CROSS-SECTIONAL STUDY, WHICH WAS CONDUCTED AT A REGIONAL UNIVERSITY AND COMMUNITY WELLNESS CENTER, INCLUDED CONVENIENCE SAMPLING OF 19 HATHA YOGA PRACTITIONERS AND 8 HEALTHY CONTROLS. USING A LEAD II ECG SYSTEM, 10 MINUTES OF ELECTROCARDIOGRAM (ECG) RECORDING WAS COLLECTED FOR EACH PARTICIPANT. ARTIFACT-FREE, 5-MINUTE SIGNALS WERE USED TO DERIVE TIME-DOMAIN AND FREQUENCY-DOMAIN MEASURES OF HRV. THE MEAN DURATION OF HATHA YOGA PRACTICE AMONG PRACTITIONERS WAS 11.47 +/- 8 YEARS. DEMOGRAPHIC AND ANTHROPOMETRIC CHARACTERISTICS DID NOT DIFFER SIGNIFICANTLY BETWEEN GROUPS. COMPARED WITH THE CONTROL GROUP, THE YOGA GROUP HAD SIGNIFICANTLY GREATER MEAN HIGH FREQUENCY (HF) POWER (859.2 +/- 1342.1 VS 175.5 +/- 121.1; P = .04) AND MEAN HF NORMALIZED UNITS (NU) (57.0 +/- 16.6 VS 36.7 +/- 13.4; P = .02) AND A SIGNIFICANTLY LOWER LOW FREQUENCY (LF)/HF RATIO (1.1 +/- 0.5 VS 2.2 +/- 1.1; P = .01). NO SIGNIFICANT INTERGROUP DIFFERENCES WERE OBSERVED FOR LF POWER, LF NU, OR ANY TIME-DOMAIN MEASURES OF HRV. THESE RESULTS LACK GENERALIZABILITY DUE TO SMALL SAMPLE SIZE AND LACK OF BLINDED ASSESSMENT OF OUTCOME MEASURES. HATHA YOGA PRACTITIONERS SHOWED PARASYMPATHETIC PREDOMINANCE COMPARED WITH HEALTHY CONTROLS. ANALYZING FREQUENCY-DOMAIN HRV METRICS ENABLES DETECTING CHANGES IN CARDIAC AUTONOMIC FUNCTION EARLIER THAN BY ANALYSIS OF TIME-DOMAIN METRICS. PARASYMPATHETIC PREDOMINANCE DEMONSTRATED IN THE YOGA GROUP SUGGESTS HATHA YOGA PRACTITIONERS MAY BE AT LOWER RISK FOR STRESS-RELATED COMORBIDITIES.	2021