The Effects of Slow Breathing during Inter-Set Recovery on Power Performance in the Barbell Back Squat.

Slow breathing (SB) reduces sympathetic nervous system activity, the heart rate (HR), and blood pressure (BP) and increases parasympathetic nervous system activity, HR variability, and oxygen saturation which may lead to quicker recovery between bouts of exercise. Therefore, the purpose of this study was to examine whether a SB technique using the 4-7-8 method between sets of barbell back squats (SQs) would attenuate drops in power and bar velocity. In a randomized, crossover design, 18 healthy resistance-trained college-aged males (age: 20.7 ± 1.4 years, body height: 178.6 ± 6.4 cm, body mass: 82.2 ± 15.0 kg, 4.5 ± 2.4 years of experience) performed 5 sets of 3 repetitions of SQs with normal breathing (CON) or SB during the 3-min recovery between sets. Peak and average power and bar velocity were assessed using a linear positioning transducer. HR recovery (RHR), systolic BP recovery (RBP), the rating of perceived exertion (RPE) and the rating of perceived recovery score (RS) were assessed after each set. There were no significant differences between conditions for peak and average power and bar velocity, RBP, RPE, and RS (p > 0.211). SB led to a greater RHR after set 2 (SB: 51.0 ± 14.9 bpm vs. CON: 44.5 ± 11.5 bpm, p = 0.025) and 3 (SB: 48.3 ± 13.5 bpm vs. CON: 37.7 ± 11.7 bpm, p = 0.006) compared to the CON condition. SB was well tolerated, did not hinder nor improve training performance and improved RHR after the middle sets of SQs. Further investigations are warranted to examine the effects of other SB techniques and to determine SB's effects on different training stimuli as well as its effects over an entire workout and post-workout recovery metrics.

A comparison of the energy demands of quadrupedal movement training to walking.

Background: Quadrupedal movement training (QMT) is a novel alternative form of exercise recently shown to improve several fitness characteristics including flexibility, movement quality, and dynamic balance. However, the specific energy demands of this style of training remain unknown. Therefore, the purpose of this study was to compare the energy expenditure (EE) of a beginner-level quadrupedal movement training (QMT) class using Animal Flow (AF) to walking, and to compare EE between segments of the AF class and gender. Methods: Participants (15 male, 15 female) completed 60-min sessions of AF, treadmill walking at a self-selected intensity (SSIT) and treadmill walking at an intensity that matched the heart rate of the AF session (HRTM). Indirect calorimetry was used to estimate energy expenditure. Results: AF resulted in an EE of 6.7 ± 1.8 kcal/min, 5.4 ± 1.0 METs, and HR of 127.1 ± 16.1 bpm (63.4 ± 8.1% of the subjects' age-predicted maximum HR), while SSIT resulted in an EE of 5.1 ± 1.0 kcal/min, 4.3 ± 0.7 METs, HR of 99.8 ± 13.5 bpm (49.8 ± 6.7% age-predicted maximum HR), and HRTM resulted in and EE of 7.6 ± 2.2 kcal/min, 6.1 ± 1.0 METs, and HR of 124.9 ± 16.3 bpm (62.3 ± 8.2% age-predicted maximum HR). Overall, EE, METs, HR and respiratory data for AF was greater than SSIT (p's < 0.001) and either comparable or slightly less than HRTM. The Flow segment showed the highest EE (8.7 ± 2.7 kcal/min), METs (7.0 ± 1.7) and HR (153.2 ± 15.7 bpm). Aside from HR, males demonstrated greater EE, METs, and respiratory values across all sessions and segments of AF than females. Conclusions: QMT using AF meets the ACSM's criteria for moderate-intensity physical activity and should be considered a viable alternative to help meet physical activity guidelines.