Effects of concurrent exercise training on body composition, systemic inflammation, and components of metabolic syndrome in inactive academics: a randomised controlled trial.

PURPOSE: Low physical activity in the academic workplace may increase the risk of cardiometabolic disease. This randomised controlled trial investigated the effect of 14 weeks of concurrent exercise training (CT) on components of metabolic syndrome, body composition, insulin resistance, and markers of systemic inflammation in inactive academics. METHODS: 59 inactive academics were randomised into a CT (n = 29) or wait-list control group (n = 30). CT performed supervised training at an onsite facility 3 times per week for 14 weeks and cardiometabolic health was assessed pre- and post-intervention. Aerobic capacity was measured via a metabolic cart. Dual-Energy X-ray Absorptiometry measured fat mass, lean mass, and central adiposity. Fasting blood samples were analysed for interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), Homeostatic Model Assessment for Insulin Resistance (HOMA-IR), glucose, and lipid profile. RESULTS: Following the intervention, there was a decrease in fat mass (mean ± SD; - 1.3 ± 1.4%), android fat mass (median (IQR); - 0.06 (0.27) kg), and visceral adipose tissue (median (IQR); - 66 (110) cm3) in CT, but not control. Lean mass (median (IQR); 1.35 (1.86) kg) and aerobic capacity (mean ± SD; 4.0 ± 3.1 mL/kg/min) increased in CT, but not in control. There were no changes in IL-6, TNF-a, HOMA-IR, glucose, or lipid profile in response to the intervention (P > 0.05). Changes in insulin resistance were positively associated with IL-6 in the control group only (coefficients [95%CI]; 5.957 [2.961, 8.953]). CONCLUSION: Implementing combined aerobic and resistance exercise training programs in academic institutions may be an appropriate intervention to increase physical activity and reduce risk factors associated with cardiometabolic disease. TRIAL REGISTRATION: The study was registered with the Australian New Zealand Clinical Trials Registry on the 23rd of April, 2019 (ACTRN12619000608167).

The effect of high-intensity aerobic interval training on markers of systemic inflammation in sedentary populations.

PURPOSE: This study examined the effects of high-intensity interval training (HIIT; 30 s sprint, 4-5 min passive recovery) and prolonged intermittent sprint training (PIST; 10 s sprint, 2-3 min moderate exercise) on the systemic inflammatory markers C-reactive protein (CRP) and tumor necrosis factor-α (TNF-α), aerobic capacity, and anthropometry in a middle-aged, sedentary population. METHODS: Fifty-five sedentary adults (age 49.2 ± 6.1 years) were randomised into HIIT (n = 20), PIST (n = 21), or a sedentary control group (CTRL n = 14). HIIT and PIST performed three training sessions per week for 9 weeks on a cycle ergometer, matched for total high-intensity time, while CTRL continued normal sedentary behaviours. Pre- and post-intervention testing involved measures of anthropometry, peak oxygen consumption (VO2peak), and venous blood collection for analyses of CRP and TNF-α. RESULTS: HIIT and PIST increased VO2peak compared to CTRL (+3.66 ± 2.23 and 3.74 ± 2.62 mL kg min-1). A group × time interaction (p = 0.042) and main effect of time (p = 0.026) were evident for waist girth, with only HIIT showing a significant reduction compared to CTRL (-2.1 ± 2.8 cm). TNF-α and CRP showed no group × time interaction or time effect (p > 0.05). CONCLUSIONS: In sedentary individuals, 9 weeks of HIIT or PIST were effective to improve aerobic capacity; however, only HIIT significantly reduced waist girth and WHR compared to CTRL. Markers of systemic inflammation remained unchanged across all groups. Accordingly, for inflammation and VO2peak, the distribution of sprints and the active or passive recovery periods are inconsequential provided that total duration of high-intensity efforts is similar.

Overtraining in Resistance Exercise: An Exploratory Systematic Review and Methodological Appraisal of the Literature.

BACKGROUND: The balance between training stress and recovery is important for inducing adaptations to improve athletic performance. However, continuously high training loads with insufficient recovery may cause fatigue to accumulate and result in overtraining. A comprehensive systematic review is required to collate overtraining literature and improve the current understanding of the mechanisms underlying functional overreaching (FOR), non-functional overreaching (NFOR) and the overtraining syndrome (OTS) in resistance training. OBJECTIVE: The objective of this systematic review was to establish markers of overtraining and elucidate the mechanisms underlying maladaptive resistance training conditions. Furthermore, this review aims to critically evaluate the methodological approaches of the overtraining literature. METHODS: A systematic literature search was performed on PubMed, Web of Science and SPORTDiscus to identify studies up to June 2019. Electronic databases were searched using terms related to resistance training and overtraining. Records were included if they attempted to induce a state of overreaching or overtraining through resistance exercise in healthy participants. RESULTS: A total of 22 studies were selected for review. Among these studies, eight resulted in decrements in performance and measured changes in performance during a follow-up period. There were four studies that reported decrease in performance yet failed to implement follow-up measures. A total of 10 studies reported no decline in performance. Overall, a lack of standardisation in methodology (follow-up performance testing) and diagnostic criteria prevents consistent determination of FOR, NFOR and OTS in resistance training. CONCLUSIONS: Few studies have appropriately established FOR, NFOR or OTS in resistance training. Overtraining may be related to frequent high-intensity and monotonous resistance training. However, no marker other than a sustained decrease in performance has been established as a reliable indicator of overtraining in resistance exercise. REGISTRATION: This systematic review was registered on the Open Science Framework (https://osf.io/) (https://doi.org/10.17605/osf.io/5bmsp).