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1.  Role of Respiration in Mind-Body Practices: Concepts from Contemporary Science and Traditional Yoga Texts 
doi:10.3389/fpsyt.2014.00167
PMCID: PMC4243490  PMID: 25505427
ancient yoga texts; psychosomatic disease; respiratory regulation; affect; relaxation; inner awareness
2.  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 naïve-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.
doi:10.12659/MSMBR.892063
PMCID: PMC4247229  PMID: 25408140
Arterial Pressure; Heart Rate; Yoga
3.  An explorative study of metabolic responses to mental stress and yoga practices in yoga practitioners, non-yoga practitioners and individuals with metabolic syndrome 
Background
Stress places a metabolic burden on homeostasis and is linked to heightened sympathetic activity, increased energy expenditure and pathology. The yogic state is a hypometabolic state that corresponds with mind-body coherence and reduced stress. This study aimed to investigate metabolic responses to stress and different yoga practices in regular yoga practitioners (YP), non-yoga practitioners (NY) and metabolic syndrome patients (MS).
Methods
YP (n = 16), NY (n = 15) and MS (n = 15) subjects underwent an experimental protocol that comprised of different 5-minute interventions including mental arithmetic stress test (MAST), alternate nostril breathing (ANB), Kapabhati breathing (KB) and meditation (Med) interspersed with 5 minutes of quiet resting (neutral condition (NC)). During the intervention periods continuous body weight adjusted oxygen consumption (VO2ml/min/kg) was measured using open circuit indirect calorimetry with a canopy hood.
Results
This is the first study to report oxygen consumption (OC) in yoga practitioners during and after MAST and the first to report both within and between different populations. The results were analysed with SPSS 16 using 3X9 mixed factorial ANOVAs. The single between-subject factor was group (YP, NY and MS), the single within-subject factor was made up of the nine intervention phases (NC1, MAST, NC2, ANB, NC3, KB, NC4, Med, NC5). The results demonstrated that the regular YP group had significantly less OC and greater variability in their OC across all phases compared to the MS group (p = .003) and NY group (p = .01). All groups significantly raised their OC during the mental arithmetic stress, however the MS group had a significantly blunted post-stress recovery whereas the YP group rapidly recovered back to baseline levels with post stress recovery being greater than either the NY group or MS group.
Conclusions
Yoga practitioners have greater metabolic variability compared to non-yoga practitioners and metabolic syndrome patients with reduced oxygen requirements during resting conditions and more rapid post-stress recovery. OC in metabolic syndrome patients displays significantly blunted post-stress recovery demonstrating reduced metabolic resilience. Our results support the findings of previous randomised trials that suggest regular yoga practice may mitigate against the effects of metabolic syndrome.
Clinical trial number
ACTRN12614001075673; Date of Registration: 07/10/2014.
doi:10.1186/1472-6882-14-445
PMCID: PMC4247158  PMID: 25398263
Yoga; Meditation; Breathing; Metabolic syndrome; Oxygen consumption; Energy Expenditure; Metabolic rate; Stress reactivity; Stress recovery
4.  Research on Traditional Medicine: What Has Been Done, the Difficulties, and Possible Solutions 
Traditional medicine (TM) is being used more frequently all over the world. However most often these are choices made by the patient. Integrating TM into mainstream health care would require research to understand the efficacy, safety, and mechanism of action of TM systems. This paper describes research done on TM and difficulties encountered in researching TM, especially when an attempt is made to conform to the model for conventional medicine. The research articles were PubMed searched and categorized as experimental, quasiexperimental, reviews, descriptive, historical, interviews, case histories, and abstract not available. The last part of the report provides suggestions to make research on TM more acceptable and useful, with the ultimate goal of integrating TM into mainstream healthcare with sufficient knowledge about the efficacy, safety, and mechanism of action of TM systems.
doi:10.1155/2014/495635
PMCID: PMC4074945  PMID: 25013445
5.  A comparative controlled trial comparing the effects of yoga and walking for overweight and obese adults 
Background
Walking and yoga have been independently evaluated for weight control; however, there are very few studies comparing the 2 with randomization.
Material/Methods
The present study compared the effects of 90 minutes/day for 15 days of supervised yoga or supervised walking on: (i) related biochemistry, (ii) anthropometric variables, (iii) body composition, (iv) postural stability, and (v) bilateral hand grip strength in overweight and obese persons. Sixty-eight participants, of whom 5 were overweight (BMI ≥25 kg/m2) and 63 were obese (BMI ≥30 kg/m2; group mean age ±S.D., 36.4±11.2 years; 35 females), were randomized as 2 groups – (i) a yoga group and (ii) a walking group – given the same diet.
Results
All differences were pre-post changes within each group. Both groups showed a significant (p<0.05; repeated measures ANOVA, post-hoc analyses) decrease in: BMI, waist circumference, hip circumference, lean mass, body water, and total cholesterol. The yoga group increased serum leptin (p<0.01) and decreased LDL cholesterol (p<0.05). The walking group decreased serum adiponectin (p<0.05) and triglycerides (p<0.05).
Conclusions
Both yoga and walking improved anthropometric variables and serum lipid profile in overweight and obese persons. The possible implications are discussed.
doi:10.12659/MSM.889805
PMCID: PMC4051462  PMID: 24878827
Yoga; Walking; Obesity; Adipokines; Lipid Profile; Anthropometry
6.  Changes in Autonomic Variables Following Two Meditative States Described in Yoga Texts 
Abstract
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.
doi:10.1089/acm.2011.0282
PMCID: PMC3546358  PMID: 22946453
8.  Effect of yoga or physical exercise on physical, cognitive and emotional measures in children: a randomized controlled trial 
Background
Previous studies have separately reported the effects of physical exercise and yoga in children, showing physical, cognitive and emotional benefits.
Objectives
The present randomized controlled trial assessed the effects of yoga or physical exercise on physical fitness, cognitive performance, self-esteem, and teacher-rated behavior and performance, in school children.
Methods
98 school children between 8 to 13 years were randomized as yoga and physical exercise groups {n = 49 each; (yoga: 15 girls, group mean age 10.4 ± 1.2 years), (physical exercise: 23 girls, group mean age 10.5 ± 1.3 years)}. Both groups were blind assessed after allocation, using: (i) the Eurofit physical fitness test battery, (ii) Stroop color-word task for children, (iii) Battle’s self-esteem inventory and (iv) the teachers’ rating of the children’s obedience, academic performance, attention, punctuality, and behavior with friends and teachers. After assessments the yoga group practiced yoga (breathing techniques, postures, guided relaxation and chanting), 45 minutes each day, 5 days a week. During this time the physical exercise group had jogging-in-place, rapid repetitive movements and relay races or games. Both groups were assessed at the end of 3 months. Data were analyzed with RM ANOVA and post-hoc tests were Bonferroni adjusted.
Results
There was one significant difference between groups. This was in social self-esteem which was higher after physical exercise compared to yoga (p < 0.05). All the changes reported below are based on after-before comparisons, within each group. Both groups showed an increase in BMI, and number of sit-ups (p < 0.001). Balance worsened in the physical exercise group, while plate tapping improved in the yoga group (p < 0.001). In the Stroop task both groups showed improved color, word- and color-word naming (p < 0.01), while the physical exercise group showed higher interference scores. Total, general and parental self-esteem improved in the yoga group (p < 0.05).
Conclusion
Yoga and physical exercise are useful additions to the school routine, with physical exercise improving social self-esteem.
Trial registration
The study was registered in the Clinical Trials Registry of India (CTRI/2012/11/003112).
doi:10.1186/1753-2000-7-37
PMCID: PMC3826528  PMID: 24199742
Yoga; Physical exercise; Physical fitness; Cognitive performance; Self-esteem; School children
10.  Changes in P300 following alternate nostril yoga breathing and breath awareness 
This study assessed the effect of alternate nostril yoga breathing (nadisuddhi pranayama) on P300 auditory evoked potentials compared to a session of breath awareness of equal duration, in 20 male adult volunteers who had an experience of yoga breathing practices for more than three months. Peak amplitudes and peak latencies of the P300 were assessed before and after the respective sessions. There was a significant increase in the P300 peak amplitudes at Fz, Cz, and Pz and a significant decrease in the peak latency at Fz alone following alternate nostril yoga breathing. Following breath awareness there was a significant increase in the peak amplitude of P300 at Cz. This suggests that alternate nostril yoga breathing positively influences cognitive processes which are required for sustained attention at different scalp sites (frontal, vertex and parietal), whereas breath awareness brings about changes at the vertex alone.
doi:10.1186/1751-0759-7-11
PMCID: PMC3679963  PMID: 23721252
Alternate nostril yoga breathing; P300; Breath awareness; Cognitive processes
12.  Yoga on Our Minds: A Systematic Review of Yoga for Neuropsychiatric Disorders 
Background: The demand for clinically efficacious, safe, patient acceptable, and cost-effective forms of treatment for mental illness is growing. Several studies have demonstrated benefit from yoga in specific psychiatric symptoms and a general sense of well-being.
Objective: To systematically examine the evidence for efficacy of yoga in the treatment of selected major psychiatric disorders.
Methods: Electronic searches of The Cochrane Central Register of Controlled Trials and the standard bibliographic databases, MEDLINE, EMBASE, and PsycINFO, were performed through April 2011 and an updated in June 2011 using the keywords yoga AND psychiatry OR depression OR anxiety OR schizophrenia OR cognition OR memory OR attention AND randomized controlled trial (RCT). Studies with yoga as the independent variable and one of the above mentioned terms as the dependent variable were included and exclusion criteria were applied.
Results: The search yielded a total of 124 trials, of which 16 met rigorous criteria for the final review. Grade B evidence supporting a potential acute benefit for yoga exists in depression (four RCTs), as an adjunct to pharmacotherapy in schizophrenia (three RCTs), in children with ADHD (two RCTs), and Grade C evidence in sleep complaints (three RCTs). RCTs in cognitive disorders and eating disorders yielded conflicting results. No studies looked at primary prevention, relapse prevention, or comparative effectiveness versus pharmacotherapy.
Conclusion: There is emerging evidence from randomized trials to support popular beliefs about yoga for depression, sleep disorders, and as an augmentation therapy. Limitations of literature include inability to do double-blind studies, multiplicity of comparisons within small studies, and lack of replication. Biomarker and neuroimaging studies, those comparing yoga with standard pharmaco- and psychotherapies, and studies of long-term efficacy are needed to fully translate the promise of yoga for enhancing mental health.
doi:10.3389/fpsyt.2012.00117
PMCID: PMC3555015  PMID: 23355825
yoga; meditation; depression; schizophrenia; cognition; ADHD; clinical trials; alternative medicine
13.  Blood pressure and purdue pegboard scores in individuals with hypertension after alternate nostril breathing, breath awareness, and no intervention 
Background
Previously alternate nostril yoga breathing (anuloma-viloma pranayama) was shown to reduce the blood pressure (BP) in people with hypertension. An elevated BP has been associated with poor performance in certain tasks requiring attention and co-ordination. The Purdue pegboard task assesses manual dexterity and eye-hand co-ordination.
Material/Methods
In the present study there were ninety participants with essential hypertension. Their ages ranged from 20 to 59 years (group average age ±S.D., 49.7±9.5 years; sixty males). Participants were randomized as three groups, with thirty participants in each group. One group practiced alternate nostril yoga breathing for 10 minutes, the second group practiced breath awareness for the same duration and the third group was given a control intervention (i.e., reading a magazine with neutral content). Assessments were taken before and after the interventions for participants of the three groups. Assessments included the blood pressure and performance in the Purdue pegboard task. Data were analyzed with a repeated measures ANOVA and post-hoc analyses were Bonferroni adjusted.
Results
Following alternate nostril breathing (ANYB) there was a significant decrease in systolic and diastolic blood pressure (p<0.001 and p<0.05), and an improvement in Purdue pegboard task scores for both hands (p<0.05), and for the right hand (p<.001). Breath awareness (the control session) also showed a significant decrease in systolic blood pressure (p<0.05). The right hand scores improved in the group reading a magazine (p<0.05).
Conclusions
The results suggest that the immediate effect of ANYB is to reduce the BP while improving the performing in a task requiring attention, bimanual dexterity and visuo-motor co-ordination.
doi:10.12659/MSM.883743
PMCID: PMC3628802  PMID: 23334063
hypertension; alternate nostril yoga breathing; blood pressure; Purdue pegboard task; attention; visuo-motor co-ordination; bi-manual dexterity
15.  Effects of Yoga on Mental and Physical Health: A Short Summary of Reviews 
This report summarizes the current evidence on the effects of yoga interventions on various components of mental and physical health, by focussing on the evidence described in review articles. Collectively, these reviews suggest a number of areas where yoga may well be beneficial, but more research is required for virtually all of them to firmly establish such benefits. The heterogeneity among interventions and conditions studied has hampered the use of meta-analysis as an appropriate tool for summarizing the current literature. Nevertheless, there are some meta-analyses which indicate beneficial effects of yoga interventions, and there are several randomized clinical trials (RCT's) of relatively high quality indicating beneficial effects of yoga for pain-associated disability and mental health. Yoga may well be effective as a supportive adjunct to mitigate some medical conditions, but not yet a proven stand-alone, curative treatment. Larger-scale and more rigorous research with higher methodological quality and adequate control interventions is highly encouraged because yoga may have potential to be implemented as a beneficial supportive/adjunct treatment that is relatively cost-effective, may be practiced at least in part as a self-care behavioral treatment, provides a life-long behavioural skill, enhances self-efficacy and self-confidence and is often associated with additional positive side effects.
doi:10.1155/2012/165410
PMCID: PMC3447533  PMID: 23008738
16.  Is yoga a suitable treatment for rheumatoid arthritis: current opinion 
We reviewed published literature regarding the use of yoga for managing rheumatoid arthritis to determine whether adequate evidence exists to suggest its usefulness as a therapy. A search for previous studies involving yoga and rheumatoid arthritis in PubMed yielded eight reports. These studies reported the benefits of yoga in the physical and mental health of patients with rheumatoid arthritis (RA), suggesting that yoga is a useful add-on therapy for RA patients. However, all studies showed limitations with respect to sample size, study design, description and duration of yoga intervention, and assessment tools and statistical methods used. Additionally, the studies did not attempt to understand the mechanisms underlying observed benefits. Hence, evidence suggests a definite role of yoga in RA improvement, reducing pain, improving function, and creating a positive mental state. However, detailed analysis and additional studies are necessary to verify these observations.
doi:10.2147/OAJSM.S25707
PMCID: PMC3781903  PMID: 24198591
bibliographic database search; PubMed; rheumatoid arthritis; yoga
17.  Yoga breathing through a particular nostril is associated with contralateral event-related potential changes 
International Journal of Yoga  2012;5(2):102-107.
Background:
In earlier studies uninostril yoga breathing was shown to influence the activity of the cerebral hemispheres differently, based on (i) auditory evoked potentials recorded from bilateral scalp sites, and (ii) performance in hemisphere-specific tasks. But change in P300 (event-related potential generated when subjects attend to and discriminate between stimuli) from bilateral scalp sites when subjects were practicing uni- and alternate-nostril breathing are yet to be explored.
Aim:
The present study was designed to determine whether or not immediately after uninostril or alternate nostril yoga breathing there would be a change in the ability to pay attention to a given stimulus.
Materials and Methods:
Twenty-nine healthy male volunteers, with ages between 20 and 45 years were randomly allocated to five sessions, viz., (i) right-, (ii) left-, (iii) alternate-nostril yoga breathing, (iv) breath awareness and (v) no intervention, each for 45 min on separate days. The P300 event related potential was recorded using an auditory oddball paradigm from sites on the left (C3) and right (C4), referenced to linked earlobes, before and after each session.
Results:
Post-hoc analysis with Bonferroni adjustment showed that the P300 peak latency was significantly lower at C3 compared to that at C4, following right nostril yoga breathing (P<0.05).
Conclusion:
These results suggest that right nostril yoga breathing facilitates the activity of contralateral (left) hemisphere, in the performance of the P300 task.
doi:10.4103/0973-6131.98220
PMCID: PMC3410187  PMID: 22869992
Contralateral changes; P300; uni-nostril yoga breathing
18.  Performance in attentional tasks following meditative focusing and focusing without meditation  
Ancient Science of Life  2012;32(1):49-53.
Background/Aims:
Ancient Indian yoga texts have described four mental states. These are caïcalatä (random thinking), ekāgratā (focusing without meditation), dhāraṇā (meditative focusing), and dhyāna (defocused meditative expansiveness). A previous study compared the performance in a cancellation task at the beginning and end of each of the four mental states (practiced for 20 minutes each, on four separate days) showed an increase in the scores after dhāraṇā Hence, the present study was designed to assess the effects of dhāraṇā (meditative focusing) and ekāgratā (focusing without meditation) on two attention tasks (i) d2 test of attention and (ii) digit symbol substitution test.
Materials and Methods:
Sixty normal healthy male volunteers with ages ranging from 17 to 38 years (group mean age ± S.D., 24.87 ± 4.95) were studied. Assessments were made before and after the practice of ekāgratā and dhāraṇā on two separate days.
Results:
After both types of focusing, there was a significant improvement in all measures of the d2 test of attention (TN, E, TN-E, E%, and CP). However, the performance in the digit symbol substitution test was better after dhāraṇā but did not change after ekāgratā.
Conclusions:
Hence, in summary, dhāraṇā (meditative focusing) and ekāgratā (focusing without meditation) produce nearly comparable results though dhāraṇā (meditative focusing) results in better incidental learning and better accuracy (as assessed by the substitution task).
doi:10.4103/0257-7941.113799
PMCID: PMC3733208  PMID: 23929995
Attention; concentration; dhāraṇā; ekāgratā; incidental learning
19.  Managing Mental Health Disorders Resulting from Trauma through Yoga: A Review 
There are many and varied types of trauma. The extent to which trauma influences the mental health of an individual depends on the nature of trauma, as well as on the individual's coping capabilities. Often trauma is followed by depression, anxiety, and PTSD. As the pharmacological remedies for these conditions often have undesirable side-effects, nonpharmacological remedies are thought of as a possible add-on treatment. Yoga is one such mind-body intervention. This paper covers eleven studies indexed in PubMed, in which mental health disorders resulting from trauma were managed through yoga including meditation. The aim was to evaluate the use of yoga in managing trauma-related depression, anxiety, PTSD and physiological stress following exposure to natural calamities, war, interpersonal violence, and incarceration in a correctional facility. An attempt has also been made to explore possible mechanisms underlying benefits seen. As most of these studies were not done on persons exposed to trauma that had practiced yoga, this is a definite area for further research.
doi:10.1155/2012/401513
PMCID: PMC3388328  PMID: 22778930
20.  Awareness about bibliographic databases among students of Ayurveda and qualified Ayurveda practitioners 
Students of Ayurveda and qualified Ayurveda practitioners were assessed for awareness about bibliographic databases. One hundred and four volunteers (age range 17–64 years; group mean±SD, 24.3 ± 7.9 years; 62 females) participated in this cross-sectional study. There were 3 groups. Group I had 60 undergraduate students of a bachelor's level course in Ayurveda, Group II had 20 graduate students of a 1-year Panchakarma course, and Group III had 24 Ayurveda physicians who were working in a yoga and Ayurveda center. An 8-question questionnaire was used for assessment. Undergraduates were found to be the best informed, followed by those who were working, while those doing post-graduation were the least well informed. The sample was from one institution; however, the findings emphasize the importance of updating the knowledge of post-graduates or those in practice.
doi:10.4103/0975-9476.96516
PMCID: PMC3371558  PMID: 22707859
Ayurveda; bibliographic databases; complementary and alternative medicine
21.  Finger dexterity and visual discrimination following two yoga breathing practices 
International Journal of Yoga  2012;5(1):37-41.
Background:
Practicing yoga has been shown to improve motor functions and attention. Though attention is required for fine motor and discrimination tasks, the effect of yoga breathing techniques on fine motor skills and visual discrimination has not been assessed.
Aim:
To study the effect of yoga breathing techniques on finger dexterity and visual discrimination.
Materials and Methods:
The present study consisted of one hundred and forty subjects who had enrolled for stress management. They were randomly divided into two groups, one group practiced high frequency yoga breathing while the other group practiced breath awareness. High frequency yoga breathing (kapalabhati, breath rate 1.0 Hz) and breath awareness are two yoga practices which improve attention. The immediate effect of high frequency yoga breathing and breath awareness (i) were assessed on the performance on the O′Connor finger dexterity task and (ii) (in) a shape and size discrimination task.
Results:
There was a significant improvement in the finger dexterity task by 19% after kapalabhati and 9% after breath awareness (P<0.001 in both cases, repeated measures ANOVA and post-hoc analyses). There was a significant reduction (P<0.001) in error (41% after kapalabhati and 21% after breath awareness) as well as time taken to complete the shape and size discrimination test (15% after kapalabhati and 15% after breath awareness; P<0.001) was also observed.
Conclusion:
Both kapalabahati and breath awareness can improve fine motor skills and visual discrimination, with a greater magnitude of change after kapalabhati.
doi:10.4103/0973-6131.91710
PMCID: PMC3276931  PMID: 22346064
Finger dexterity; shape and size discrimination; yoga breathing
22.  Effect of Yoga and Ayurveda on Duchenne Muscular Dystrophy 
Indian Journal of Palliative Care  2011;17(2):169-170.
doi:10.4103/0973-1075.84544
PMCID: PMC3183612  PMID: 21976863
23.  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.
doi:10.1186/1751-0759-5-4
PMCID: PMC3088536  PMID: 21486495
24.  Effect of one week of yoga on function and severity in rheumatoid arthritis 
BMC Research Notes  2011;4:118.
Background
Previous studies have shown that yoga practice improved the hand grip strength in patients with rheumatoid arthritis (RA).
Findings
Sixty-four participants with RA (group average age ± S.D., 46.5 ± 9.6 years; 47 females) were assessed at the beginning and end of a one week yoga program. The Stanford Health Assessment Questionnaire (HAQ), hand grip strength, rheumatoid factor, and C-reactive protein levels were assessed on the first and last day and compared using a t-test for paired data. All participants showed reduced disability scores of the HAQ and rheumatoid factor levels, with an increase in bilateral hand grip strength in male participants alone.
Conclusions
This single group study indicated that a brief intensive yoga program was beneficial in RA, with decreased disability, better functionality and changes in the rheumatoid factor levels suggesting improvement.
doi:10.1186/1756-0500-4-118
PMCID: PMC3083351  PMID: 21481278
25.  Brainstem auditory-evoked potentials in two meditative mental states 
International Journal of Yoga  2010;3(2):37-41.
Context:
Practicing mental repetition of “OM” has been shown to cause significant changes in the middle latency auditory-evoked potentials, which suggests that it facilitates the neural activity at the mesencephalic or diencephalic levels.
Aims:
The aim of the study was to study the brainstem auditory-evoked potentials (BAEP) in two meditation states based on consciousness, viz. dharana, and dhyana.
Materials and Methods:
Thirty subjects were selected, with ages ranging from 20 to 55 years (M=29.1; ±SD=6.5 years) who had a minimum of 6 months experience in meditating “OM”. Each subject was assessed in four sessions, i.e. two meditation and two control sessions. The two control sessions were: (i) ekagrata, i.e. single-topic lecture on meditation and (ii) cancalata, i.e. non-targeted thinking. The two meditation sessions were: (i) dharana, i.e. focusing on the symbol “OM” and (ii) dhyana, i.e. effortless single-thought state “OM”. All four sessions were recorded on four different days and consisted of three states, i.e. pre, during and post.
Results:
The present results showed that the wave V peak latency significantly increased in cancalata, ekagrata and dharana, but no change occurred during the dhyana session.
Conclusions:
These results suggested that information transmission along the auditory pathway is delayed during cancalata, ekagrata and dharana, but there is no change during dhyana. It may be said that auditory information transmission was delayed at the inferior collicular level as the wave V corresponds to the tectum.
doi:10.4103/0973-6131.72628
PMCID: PMC2997230  PMID: 21170228
Brainstem auditory-evoked potential; cancalata; dharana; dhyana; ekagrata

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