Maximal strength training : the impact of eccentric overload

The search for the most potent strength training intervention is continuous. Maximal strength training (MST) yields large improvements in force-generating capacity (FGC), largely attributed to efferent neural drive enhancement. However, it remains elusive whether eccentric overload, before the concentric phase, may augment training-induced neuromuscular adaptations. A total of 53 23 ± 3 (SD)-yr-old untrained males were randomized to either a nontraining control group (CG) or one of two training groups performing leg press strength training with linear progression, three times per week for 8 wk. The first training group carried out MST with four sets of four repetitions at ~90% one-repetition maximum (1RM) in both action phases. The second group performed MST with an augmented eccentric load of 150% 1RM (eMST). Measurements were taken of 1RM and rate of force development (RFD), countermovement jump (CMJ) performance, and evoked potentials recordings [V-wave (V) and H-reflex (H) normalized to M-wave (M) in musculus soleus]. 1RM increased from 133 ± 16 to 157 ± 23 kg and 123 ± 18 to 149 ± 22 kg and CMJ by 2.3 ± 3.6 and 2.2 ± 3.7cm for MST and eMST, respectively (all P < 0.05). Early, late, and maximal RFD increased in both groups [634–1,501 N/s (MST); 644–2,111 N/s (eMST); P < 0.05]. These functional improvements were accompanied by increased V/M-ratio (MST: 0.34 ± 0.11 to 0.42 ± 14; eMST: .36 ± 0.14 to 0.43 ± 13; P < 0.05). Resting H/M-ratio remained unchanged. Training-induced improvements did not differ. All increases, except for CMJ, were different from the CG. MST is an enterprise for large gains in FGC and functional performance. Eccentric overload did not induce additional improvements, suggesting firing frequency and motor unit recruitment during MST may be maximal.publishedVersio

High-Intensity Interval Training in Patients with Substance Use Disorder

Patients with substance use disorder (SUD) suffer a higher risk of cardiovascular disease and other lifestyle diseases compared to the general population. High intensity training has been shown to effectively reduce this risk, and therefore we aimed to examine the feasibility and effect of such training in SUD patients in clinical treatment in the present study. 17 males and 7 females (32 ± 8 yr) in treatment were randomized to either a training group (TG), treadmill interval training in 4 × 4 minutes at 90–95% of maximal heart rate, 3 days a week for 8 weeks, or a conventional rehabilitation control group (CG). Baseline values for both groups combined at inclusion were 44 ± 8 (males) and 34 ± 9 (females) mL · min−1 · kg−1, respectively. 9/12 and 7/12 patients completed the TG and CG, respectively. Only the TG significantly improved (15 ± 7%) their maximal oxygen consumption (VO2max), from 42.3 ± 7.2 mL · min−1 · kg−1 at pretest to 48.7 ± 9.2 mL · min−1 · kg−1 at posttest. No between-group differences were observed in work economy, and level of insomnia (ISI) or anxiety and depression (HAD), but a significant within-group improvement in depression was apparent for the TG. High intensity training was feasible for SUD patients in treatment. This training form should be implemented as a part of the rehabilitation since it, in contrast to the conventional treatment, represents a risk reduction for cardiovascular disease and premature death

Maximal strength training as a physical rehabilitation for patients with substance use disorder; a randomized controlled trial

Background:Patients with substance use disorder (SUD) suffer from multiple health and psychosocial problems.Because poor physical capacities following an inactive lifestyle may indeed contribute to these problems, physicaltraining is often suggested as an attractive supplement to conventional SUD treatment. Strength training is shownto increase muscle strength and effectively improve health and longevity. Therefore we investigated the feasibilityand effect of a maximal strength training intervention for SUD patients in clinical treatment.Methods:16 males and 8 females were randomized into a training group (TG) and a control group (CG). The TGperformed lower extremities maximal strength training (85-90 % of 1 repetition maximum (1RM)) 3 times a weekfor 8 weeks, while the CG participated in conventional clinical activities.Results:The TG increased hack squat 1RM (88 ± 54 %), plantar flexion 1RM (26 ± 20 %), hack squat rate of forcedevelopment (82 ± 29 %) and peak force (11 ± 5 %). Additionally, the TG improved neural function, expressed asvoluntary V-wave (88 ± 83 %). The CG displayed no change in any physical parameters. The TG also reduced anxietyand insomnia, while the CG reduced anxiety.Conclusion:Maximal strength training was feasible for SUD patients in treatment, and improved multiple riskfactors for falls, fractures and lifestyle related diseases. As conventional treatment appears to have no effect onmuscle strength, systematic strength training should be implemented as part of clinical practice