Key characteristics and habits of the recreational opioid user.

Objective: To identify key characteristics and habits of recreational opioid users.

Design: The data were compiled from volunteers who participated in clinical studies at a contract research organization in Toronto, Ontario, Canada.

Interventions: Data were collected from 5,018 male and female recreational opioid users via telephone and face-to-face screening interviews.

The effect of ARC ablation on skeletal muscle morphology, function, and apoptotic signaling during aging.

Augmented apoptotic signaling can result in degradation of skeletal muscle proteins and loss of myonuclei, ultimately contributing to muscle atrophy and contractile dysfunction. Apoptosis repressor with caspase recruitment domain (ARC) is an anti-apoptotic protein highly expressed in skeletal muscle. Here we examined the role of ARC on age-related skeletal muscle apoptosis and wasting by utilizing an ARC-deficient mouse model.

Resveratrol supplementation does not augment performance adaptations or fibre-type-specific responses to high-intensity interval training in humans.

The present study examined the effect of concurrent exercise training and daily resveratrol (RSV) supplementation (150 mg) on training-induced adaptations following low-dose high-intensity interval training (HIIT). Sixteen recreationally active (∼22 years, ∼51 mL·kg(-1)·min(-1)) men were randomly assigned in a double-blind fashion to either the RSV or placebo group with both groups performing 4 weeks of HIIT 3 days per week. Before and after training, participants had a resting muscle biopsy taken, completed a peak oxygen uptake test, a Wingate test, and a submaximal exercise test.

Fibre-specific responses to endurance and low volume high intensity interval training: striking similarities in acute and chronic adaptation.

The current study involved the completion of two distinct experiments. Experiment 1 compared fibre specific and whole muscle responses to acute bouts of either low-volume high-intensity interval training (LV-HIT) or moderate-intensity continuous endurance exercise (END) in a randomized crossover design. Experiment 2 examined the impact of a six-week training intervention (END or LV-HIT; 4 days/week), on whole body and skeletal muscle fibre specific markers of aerobic and anaerobic capacity.