Hybrid-type, multicomponent interval training upregulates musculoskeletal fitness of adults with overweight and obesity in a volume-dependent manner: A 1-year dose-response randomised controlled trial.

This study examined the dose-response effects of a 1-year hybrid-type, multicomponent interval training programme (DoIT) on various musculoskeletal fitness parameters in inactive overweight and obese adults in a gym setting. Ninety-seven middle-aged (44.8 ± 5.2 years) individuals with overweight/obesity (31.2 ± 5.7 kg/m2) (66% female) were randomly assigned to the following groups: (i) no-intervention control (CON, n = 29), (ii) DoIT performed once weekly (DoIT-1, n = 24), (iii) DoIT performed twice weekly (DoIT-2, n = 23) and (iv) DoIT performed thrice weekly (DoIT-3, n = 21). DoIT was a time-efficient, intermittent-based, multicomponent exercise protocol using progressive loaded fundamental movement patterns with prescribed work-to-rest intervals (1:3-2:1) in a circuit format (2-3 rounds). Muscular strength, muscular endurance, flexibility, passive range of motion (PRoM), static balance and functional movement screen (FMS®) were assessed at baseline, 6 and 12 months following intervention. At post-training, all exercise groups exhibited superior changes than CON in (i) muscular strength (+13%-38%, p < 0.001); (ii) muscular endurance (+42%-159%, p < 0.001); (iii) flexibility (+12%-42%, p < 0.001); (iv) PRoM (+6%-50%, p = 0.001-0.026); (v) static balance (+61%-163%, p < 0.001); and (vi) FMS (+18%-39%, p < 0.001). Although a single exercise session/week improved musculoskeletal fitness, changes demonstrated a step-wise improvement with two and three sessions/week suggesting a dose-dependent response. The response rate to training was 100% for all exercise groups. These findings suggest that a multicomponent exercise approach incorporating bodyweight drills and resistance-based alternative modes performed under real-world conditions may improve several musculoskeletal fitness indicators in a dose-dependent manner in inactive, middle-aged adults with overweight/obesity.Trial registration: ClinicalTrials.gov identifier: NCT03759951.

Extended Match Time Exacerbates Fatigue and Impacts Physiological Responses in Male Soccer Players.

PURPOSE: This study evaluated how extended match time (90 + 30 min) affected physiological responses and fatigue in male soccer players. METHODS: Twenty competitive players (mean ± SD: age, 20 ± 1 yr; maximal oxygen uptake, 59 ± 4 mL·min -1 ·kg -1 ) completed an experimental match with their activity pattern and heart rate assessed throughout the game, whereas countermovement jump performance and repeated sprint ability were tested and quadriceps muscle biopsies and venous blood samples were taken at baseline and after 90 and 120 min of match play. RESULTS: Less high-intensity running (12%) was performed in extra time in association with fewer intense accelerations and decelerations per minute compared with normal time. Peak sprint speed was 11% lower in extra time compared with normal time, and fatigue also manifested in impaired postmatch repeated sprint ability and countermovement jump performance (all P < 0.05). Muscle glycogen declined from 373 ± 59 mmol·kg -1 dry weight (dw) at baseline to 266 ± 64 mmol·kg -1 dw after 90 min, with a further decline to 186 ± 56 mmol·kg -1 dw after extra time ( P < 0.05) and with single-fiber analyses revealing depleted or very low glycogen levels in ~75% of both slow and fast twitch fibers. Blood glucose did not change during the first 90-min but declined ( P < 0.05) to 81 ± 8 mg·dL -1 after extra time. Plasma glycerol and ammonia peaked at 236 ± 33 mg·dL -1 and 75 ± 21 µmol·L -1 after the extra period. CONCLUSIONS: These findings demonstrate exacerbated fatigue after extra time compared with normal time, which seems to be associated with muscle glycogen depletion, reductions in blood glucose levels, and hyperammonemia. Together, this points to metabolic disturbances being a major part of the integrated and multifaceted fatigue response during extended soccer match play.

Muscle metabolism and impaired sprint performance in an elite women's football game.

The present study examined skeletal muscle metabolism and changes in repeated sprint performance during match play for n = 20 competitive elite women outfield players. We obtained musculus vastus lateralis biopsies and blood samples before, after, and following intense periods in each half of a friendly match, along with 5 × 30-meter sprint tests and movement pattern analyses (10-Hz S5 Global Positioning System [GPS]). Muscle glycogen decreased by 39% and 42% after an intense period of the second half and after the match, respectively, compared to baseline (p < 0.05). Post-match, 80% type I fibers and 69% type II fibers were almost empty or completely empty of glycogen. Muscle lactate was higher (p < 0.05) after the intense period of the first half and post-match compared to baseline (14.3 ± 4.6 (±SEM) and 12.9 ± 5.7 vs. 6.4 ± 3.7 mmol/kg d.w.). Muscle phosphocreatine was reduced (p < 0.05) by 16% and 12%, respectively, after an intense period in the first and second half compared to baseline. Blood lactate and glucose increased during the match and peaked at 8.4 ± 2.0 and 7.9 ± 1.2 mmol/L, respectively. Mean 5 × 30 m sprint time declined by 3.2 ± 1.7 and 7.0 ± 2.1% after the first and second half, respectively, and 4.7 ± 1.6% (p < 0.05) after an intense period in the first half compared to baseline. In conclusion, match play in elite female football players resulted in marked glycogen depletion in both fiber types, which may explain fatigue at the end of a match. Repeated sprint ability was impaired after intense periods in the first half and after both halves, which may be associated with the observed muscle metabolite perturbations.

Dose-response effects of high-intensity interval neuromuscular exercise training on weight loss, performance, health and quality of life in inactive obese adults: Study rationale, design and methods of the DoIT trial.

Obesity is associated with high mortality and morbidity rates and low levels of quality of life among adults globally. It is critical to examine evidence-based practices for developing lifestyle behavioral changes such as physical movement and structured exercise training. The DoIT protocol, a high-intensity interval exercise training (HIIT) program, effectively reduces body mass, alters energy balance, and improves performance of obese adults with a high adherence rate. This study aims to determine the dose-response effects of the DoIT protocol on body composition, health, performance and quality of life in sedentary obese adults. This study will recruit 88 sedentary, obese males and females (BMI 25.0-34.9; 30-50 years) who will be randomly assigned to one of four groups: (i) control (n = 22), (ii) one session/week (n = 22), (iii) two sessions/week (n = 22) or (iv) three sessions/week (n = 22). DoIT will use a supervised, circuit-type (1-3 rounds), functional/neuromotor and progressive exercise program for 12 months. DoIT incorporates 8-12 multi-planar, fundamental and complex, whole body movements and uses bodyweight and alternative exercise modes as a resistance. DoIT utilizes prescribed work-to-rest ratios which will be varied every four weeks. Each session will last less than 30 min. DoIT will be implemented for a year and its effects on body mass and body composition, physical fitness, functional capacity, bone health, leptin, adiponectin, blood lipids, glycemic control, inflammation, oxidative stress and quality of life will be assessed. The outcomes of the proposed study will provide insight on optimal exercise prescription guidelines for such HIIT-type exercise protocols for overweight or obese individuals.