Full-Body Circuit Training Improves Body Composition and Cardiorespiratory Fitness in Overweight Sedentary Adults – A Randomized Controlled Trial

Obesity and low cardiorespiratory fitness are major risk factors for numerous non-communicable diseases and mortality, and efficient treatment protocols to counteract these conditions are highly warranted. We evaluated the effect of high-intensity circuit training (CIT) on body composition and cardiorespiratory fitness of sedentary overweight individuals. Cardiorespiratory and body composition were assessed before and after a 8-week circuit training (CIT; four sessions of full-body CIT per week; age, 38 ± 9 years old; height, 174 ± 10 cm; body mass, 93.1 ± 22.2 kg; n = 32), and 8-week inactiv-ity (CON; neither training nor lifestyle changes from week; 0–8 age, 39 ± 7 years old, height, 168 ± 8 cm, body mass, 89.5 ± 17.5 kg; n = 33). The two-way repeated-measures ANOVA revealed moderate to large reductions were observed in body mass, BMI, and fat percentage after CIT (d=0.43–0.81; P<0.05). In contrast, all body composition parameters remained stable after 8-week inactivity (P<0.05). A small to moderate group x moment interaction was found for body mass, BMI and % fat (d=0.10–0.60; P<0.05). Small improvements in VO2max were observed after CIT (d=0.48 [0.11–0.85]; P=0.010), while small to moderate reductions were observed in VO2max and PV were observed after inactivity (d=0.47 [0.11–0.83] and 0.64 [0.26–1.01], respectively; P<0.05). A small moment x group interaction was observed for VO2max (d= 0.19 [0.13–0.26]; P<0.001). Our findings suggest that 8-week of full-body circuit training may improve cardiorespiratory fitness and body composition in sedentary overweight individuals

Comparison between two types of anaerobic speed endurance training in competitive soccer players

The purpose of the present study was to examine the effects of additional in-season speed endurance production versus speed endurance maintenance training regimes on performance in competitive male soccer players. In a randomised controlled trial 18 male sub-elite players were exposed to additional speed endurance production (SEP) or speed endurance maintenance (SEM) training (two additional sessions/wk for 4 weeks) during the competitive season. Players performed the Yo-Yo intermittent recovery level 2 test (YYIR2) and a repeated sprint test (RST) pre- and post-intervention. Yo-Yo IR2 performance increased (p<0.001) by 50 ± 8% and 26 ± 5% in SEP and SEM, respectively, with greater (p=0.03) improvement in SEP. RST performance improved by 2.1 ± 0.3% and 1.3 ± 0.4% in SEP and SEM, respectively, while the RST fatigue index decreased (4.4 ± 0.8 to 3.4 ± 0.5%; p<0.04) in SEP only. Peak and average speed during training were higher (p<0.001) in SEP than in SEM (24.5 ± 0.3 vs 19.2 ± 0.3 and 15.5 ± 0.1 km·h-1 vs 9.4 ± 0.1 km·h-1). Additional in-season anaerobic speed endurance production and maintenance training improves high-intensity exercise performance in competitive soccer players with superior effects of speed endurance production training

Sodium bicarbonate intake improves high-intensity intermittent exercise performance in trained young men

BACKGROUND: Sodium bicarbonate intake has been shown to improve exercise tolerance, but the effects on high-intensity intermittent exercise are less clear. Thus, the aim of the present study was to determine the effect of sodium bicarbonate intake on Yo-Yo intermittent recovery test level 2 performance in trained young men. METHOD: Thirteen men aged 23 ± 1 year (height: 180 ± 2 cm, weight: 78 ± 3 kg; VO(2)max: 61.3 ± 3.3 mlO(2) · kg(−1) · min(−1); means ± SEM) performed the Yo-Yo intermittent recovery test level 2 (Yo-Yo IR2) on two separate occasions in randomized order with (SBC) and without (CON) prior intake of sodium bicarbonate (0.4 g · kg(−1) body weight). Heart rate and rating of perceived exertion (RPE) were measured during the test and venous blood samples were taken frequently. RESULTS: Yo-Yo IR2 performance was 14 % higher (P = 0.04) in SBC than in CON (735 ± 61 vs 646 ± 46 m, respectively). Blood pH and bicarbonate were similar between trials at baseline, but higher (P = 0.003) immediately prior to the Yo-Yo IR2 test in SBC than in CON (7.44 ± 0.01 vs 7.32 ± 0.01 and 33.7 ± 3.2 vs 27.3 ± 0.6 mmol · l(−1), respectively). Blood lactate was 0.9 ± 0.1 and 0.8 ± 0.1 mmol · l(−1) at baseline and increased to 11.3 ± 1.4 and 9.4 ± 0.8 mmol · l(−1) at exhaustion in SBC and CON, respectively, being higher (P = 0.03) in SBC. Additionally, peak blood lactate was higher (P = 0.02) in SBC than in CON (11.7 ± 1.2 vs 10.2 ± 0.7 mmol · l(−1)). Blood glucose, plasma K(+) and Na(+) were not different between trials. Peak heart rate reached at exhaustion was 197 ± 3 and 195 ± 3 bpm in SBC and CON, respectively, with no difference between conditions. RPE was 7 % lower (P = 0.003) in SBC than in CON after 440 m, but similar at exhaustion (19.3 ± 0.2 and 19.5 ± 0.2). CONCLUSION: In conclusion, high-intensity intermittent exercise performance is improved by prior intake of sodium bicarbonate in trained young men, with concomitant elevations in blood alkalosis and peak blood lactate levels, as well as lowered rating of perceived exertion

Evaluating a nationwide recreational football intervention: Recruitment, attendance, adherence, exercise intensity, and health effects

The present study evaluated a nationwide exercise intervention with Football Fitness in a small-scale society. In all, 741 adult participants (20–72 yrs) were successfully recruited for Football Fitness training in local football clubs, corresponding to 2.1% of the adult population. A preintervention test battery including resting heart rate (RHR), blood pressure, and body mass measurements along with performance tests (Yo-Yo Intermittent Endurance level 1 (Yo-Yo IE1), the Arrowhead Agility Test, and the Flamingo Balance Test) were performed (n=502). Training attendance (n=310) was 1.6 ± 0.2 sessions per week (range: 0.6–2.9), corresponding to 28.8 ± 1.0 sessions during the 18 wk intervention period. After 18 wks mean arterial pressure (MAP) was −2.7 ± 0.7 mmHg lower (P<0.05; n=151) with even greater (P<0.05) reductions for those with baseline MAP values >99 mmHg (−5.6 ± 1.5 mmHg; n=50). RHR was lowered (P<0.05) by 6 bpm after intervention (77 ± 1 to 71 ± 1 bpm). Yo-Yo IE1 performance increased by 41% (540 ± 27 to 752 ± 45 m), while agility and postural balance were improved (P<0.05) by ~6 and ~45%, respectively. In conclusion, Football Fitness was shown to be a successful health-promoting nationwide training intervention for adult participants with an extraordinary recruitment, a high attendance rate, moderate adherence, high exercise intensity, and marked benefits in cardiovascular health profile and fitness

Ergogenic effects of caffeine and sodium bicarbonate supplementation on intermittent exercise performance preceded by intense arm cranking exercise

BACKGROUND: Caffeine and sodium bicarbonate ingestion have been suggested to improve high-intensity intermittent exercise, but it is unclear if these ergogenic substances affect performance under provoked metabolic acidification. To study the effects of caffeine and sodium bicarbonate on intense intermittent exercise performance and metabolic markers under exercise-induced acidification, intense arm-cranking exercise was performed prior to intense intermittent running after intake of placebo, caffeine and sodium bicarbonate. METHODS: Male team-sports athletes (n = 12) ingested sodium bicarbonate (NaHCO(3); 0.4 g.kg(−1) b.w.), caffeine (CAF; 6 mg.kg(−1) b.w.) or placebo (PLA) on three different occasions. Thereafter, participants engaged in intense arm exercise prior to the Yo-Yo intermittent recovery test level-2 (Yo-Yo IR2). Heart rate, blood lactate and glucose as well as rating of perceived exertion (RPE) were determined during the protocol. RESULTS: CAF and NaHCO(3) elicited a 14 and 23% improvement (P < 0.05), respectively, in Yo-Yo IR2 performance, post arm exercise compared to PLA. The NaHCO(3) trial displayed higher [blood lactate] (P < 0.05) compared to CAF and PLA (10.5 ± 1.9 vs. 8.8 ± 1.7 and 7.7 ± 2.0 mmol.L(−1), respectively) after the Yo-Yo IR2. At exhaustion CAF demonstrated higher (P < 0.05) [blood glucose] compared to PLA and NaHCO(3) (5.5 ± 0.7 vs. 4.2 ± 0.9 vs. 4.1 ± 0.9 mmol.L(−1), respectively). RPE was lower (P < 0.05) during the Yo-Yo IR2 test in the NaHCO(3) trial in comparison to CAF and PLA, while no difference in heart rate was observed between trials. CONCLUSIONS: Caffeine and sodium bicarbonate administration improved Yo-Yo IR2 performance and lowered perceived exertion after intense arm cranking exercise, with greater overall effects of sodium bicarbonate intake

High-intensity intermittent swimming improves cardiovascular health status for women with mild hypertension

To test the hypothesis that high-intensity swim training improves cardiovascular health status in sedentary premenopausal women with mild hypertension, sixty-two women were randomized into high-intensity (n=21; HIT), moderate-intensity (n=21; MOD), and control groups (n=20; CON). HIT performed 6–10 × 30 s all-out swimming interspersed by 2 min recovery and MOD swam continuously for 1 h at moderate intensity for a 15-week period completing in total 44±1 and 43±1 sessions, respectively. In CON, all measured variables were similar before and after the intervention period. Systolic BP decreased (P<0.05) by 6±1 and 4±1 mmHg in HIT and MOD; respectively. Resting heart rate declined (P<0.05) by 5±1 bpm both in HIT and MOD, fat mass decreased (P<0.05) by 1.1±0.2 and 2.2±0.3 kg, respectively, while the blood lipid profile was unaltered. In HIT and MOD, performance improved (P<0.05) for a maximal 10 min swim (13±3% and 22±3%), interval swimming (23±3% and 8±3%), and Yo-Yo IE1 running performance (58±5% and 45±4%). In conclusion, high-intensity intermittent swimming is an effective training strategy to improve cardiovascular health and physical performance in sedentary women with mild hypertension. Adaptations are similar with high- and moderate-intensity training, despite markedly less total time spent and distance covered in the high-intensity group