News & Views from the Editor-in-Chief: Andrew M. Jones
.jpg)
Another month, and another three selections from a jam-packed issue of MSSE. This month's tasty trio focus on the potential importance of resistance training for prostate cancer patients, the role of testosterone in metabolic adaptations during energy deficit, and the influence of work interval duration on fatigue development during interval training.
Androgen deprivation therapy (ADT) can substantially improve survival in (locally) advanced prostate cancer patients. However, the concomitant decline in androgen levels has numerous adverse effects, which include the loss of muscle mass, gain of fat mass, and a decline in both functional and metabolic health. In 'Resistance Exercise Training Increases Muscle Mass and Strength in Prostate Cancer Patients on Androgen Deprivation Therapy', Houben et al. show that resistance exercise training during ADT can prevent many of these adverse effects. Resistance exercise training was able to increase muscle mass and strength despite the decline in circulating androgen levels and attenuate the gain in fat mass and the decline in aerobic capacity. These positive exercise effects strongly support the implementation of resistance exercise training as part of the standard care for prostate cancer patients on ADT.
In 'Metabolic Adaptation and Substrate Oxidation Unaffected by Exogenous Testosterone Administration during Energy Deficit in Men', Margolis et al. demonstrated that, compared to placebo, weekly injections of 200 mg of testosterone enanthate maintained oxygen carrying capacity and nitrogen balance during 28 days of a 55% diet- and exercise-induced energy deficit. Despite these differences, testosterone had no effect on whole-body energy expenditure and carbohydrate, fat, or protein oxidation during energy deficit. Lack of an effect of testosterone was corroborated by increases in skeletal muscle transcriptional regulation of energy sensing, mitochondrial biogenesis, and fat and protein metabolism independent of treatment. These data indicate that in the context of diet- and exercise-induced energy deficit, whole-body and skeletal muscle metabolic adaptations are largely independent of testosterone treatment.
The intensity, duration, and distribution of work and recovery phases during high-intensity interval training (HIIT) is a critical modulatory factor in the development of performance fatigability. In 'Shorter High-Intensity Cycling Intervals Reduce Performance and Perceived Fatigability at Work-Matched but not Task Failure', McClean et al. demonstrated that, despite being matched for work-to-rest ratio, HIIT protocols with shorter work intervals elicited a four-fold increase in exercise tolerance and mitigated performance fatigability and perceptual responses when matched for work completed, though not at task failure. Considering that metabolic fluctuations and the attributes of performance fatiguability are linked to the metabolic signaling for adaptations, it is critical that HIIT characteristics such as the work-to-rest ratio be considered in an individualized approach to prescribing HIIT with respect to the desired psychophysiological adaptation.
Andrew M. Jones
University of Exeter
