Is Weekly Frequency of Yoga Practice Sufficient? Physiological Effects of Hatha Yoga Among Healthy Novice Women

High-intensity interval training vs. yoga in improving binge eating and physical fitness in inactive young females

Yoga is effective in binge eating disorder (BED) treatment, but it does not seem effective enough to improve low physical fitness. In contrast, high-intensity interval training (HIIT) is effective in improving physical fitness but has never been studied in the context of BED. In the study, 47 young inactive females with mild to moderate BED were recruited and randomly assigned to a HIIT group (HIIT), a Yoga group (YG), or a control group (CG; age, 19.47 ± 0.74, 19.69 ± 0.874, and 19.44 ± 0.63 years; BMI, 21.07 ± 1.66, 21.95 ± 2.67, and 20.68 ± 2.61 kg/m2, respectively). The intervention groups participated in 8-week specific exercises, while the CG maintained their usual daily activity. Before and after the training, participants were evaluated for BED using the binge eating scale (BES) and for physical fitness. The obtained data were compared within groups and between groups, and a correlation analysis between BES and physical fitness parameters was performed. After the training, the YG presented significant improvements in BES (- 20.25%, p = 0.006, ηp2 = 0.408), fat mass (FM, - 3.13%, p = 0.033, ηp2 = 0.269), and maximal oxygen consumption (VO2max, 11.51%, p = 0.000, ηp2 = 0.601), whereas the HIIT showed significant improvements in body weight (BW, - 1.78%, p = 0.006, ηp2 = 0.433), FM (- 3.94%, p = 0.033, ηp2 = 0.285), and BMI (- 1.80%, p = 0.006, ηp2 = 0.428), but not in BES. Comparisons between groups revealed that both HIIT and YG had significantly higher VO2max levels than CG (HIIT 12.82%, p = 0.006, ηp2 = 0.088; YG: 11.90%, p = 0.009, ηp2 = 0.088) with no difference between HIIT and YG. Additionally, YG presented significantly lower BES than both HIIT (15.45%, p = 0.02, ηp2 = 0.03) and CG (11.91%, p = 0.022, ηp2 = 0.03). In conclusion, Yoga is an effective treatment for BED, but HIIT is not, despite its high efficacy in improving physical fitness.

A 6-minute protocol, combining mental imagery practices and breathing exercises, promotes hand-grip strength in firefighters: a series of "N-of-1" trials

BACKGROUND

To carry out their victim rescue and fire-fighting missions, firefighters perform high levels of physical exertion and among them strenuous muscular activity. A specific mental preparation protocol that could induce better strength performance throughout their 24-hour schedule is a major issue for firefighters.

OBJECTIVE

This case report aims to examine whether a 6-minute Intervention combining mental imagery practices and breathing exercises, specifically designed to be used while travelling between the fire station and the mission site, would be able to promote maximum strength performance.

METHODS

A series of three Single Case Experimental Designs (SCED) was conducted in single blind design to investigate the effects of repeated challenge-withdrawals between the Intervention and the Baseline on the maximum voluntary isometric contraction (MVIC) strength of the hand-grip.

RESULTS

Data analyses revealed that 62.5% to 100% of the hand-grip strength values during the Intervention periods were greater than or equal to the maximum data point recorded in the Baseline periods. The effect sizes of these highlighted increases of the hand-grip strength performance revealed by the percentage of non-overlapping data (PND) were 75% i.e., moderately effective on average.

CONCLUSIONS

Such a "psyching-up" practice before an upcoming muscular activity can promote muscular strength in firefighters. These results have led French firefighter departments to integrate the teaching of these practices into the initial instruction of firefighters, and remains to be confirmed by a randomised control trial.

Effects of a complex yoga-based intervention on physical characteristics

Empirical studies on yoga have shown that regular practice can have a beneficial effect on risk factors of cardiovascular diseases; also, it can decrease body weight, body fat and increase muscle mass. Positive effects on balance and flexibility were also reported. This study evaluated the impact of a 3-month complex yoga-based program, including physical exercises, education, and social support, with a quasi-randomized design in a middle-aged community sample. The intervention group consisted of 46 participants while the passive control group was 29 participants. The intervention group showed a significant increase in core muscle strength and hamstring flexibility and a decrease in body  fat. No significant changes were found concerning risk factors of cardiovascular diseases, body weight, muscle mass, balancing ability, and dietary habits. A 3-month yoga intervention cannot substantially impact the cardiovascular system and body weight control in middle-aged adults.

The effect of 10-week long yoga training on interoceptive abilities: cross-sectional and longitudinal investigation of cardiac and gastric accuracy

Based on their characteristics, it is likely that mind-body techniques develop interoception, the perception of bodily state. Nevertheless, findings on mindfulness, meditation, yoga, and body scan techniques are inconclusive. Additionally, the methodological scope is not exhaustive, neither in terms of the intervention nor the applied measure of interoception. This study investigated for the first time the effect of regular yoga training on cardiac and gastric perceptual ability (measured with the mental heartbeat tracking task and the water load task, respectively). With the involvement of 90 female university students (yoga group n = 57, control group n = 33) we did not find any connection between baseline heartbeat perception score and gastric fullness. Moreover, the applied 10-week-long regular yoga training did not develop any of the measured interoceptive abilities. We conclude that yoga might develop other abilities than these specific sensations. Very probably, the measured cardiac and gastric perceptual abilities do not represent bodily sensations in general. It would be worth to investigate, however, the effect of longer yoga training on interoception.