John A. Hawley’s research while affiliated with Australian Catholic University and other places

This article provides a recap of the 10 Questions/10 Experts session at the 2024 American College of Sports Medicine Annual Meeting. Each of the speakers considered the validity of common “myths,” while providing evidence-based opinions to support, or, bust, myths addressing the following questions: (1) Would 100 g/hr of carbohydrate be advisable for the Olympic Cycling Road race? (2) Is there an advantage in the marathon of ingesting bicarbonate as a hydrogel product? (3) Can genotyping be used to individualize caffeine supplementation in football? (4) Should low fluid consumers drink more to improve 1,500-m track performance? (5) Do urinary markers of dehydration predict poor basketball performance? (6) Do placebo effects influence 10-km track performance? (7) Should combat athletes make weight using glucagon-like peptide-1 receptor agonists? (8) Would crushed ice ingestion help tennis umpires make better decisions in the heat? (9) Are collagen supplements useful to reduce tendon and ligament injuries in volleyball? and (10) Should female athletes plan their training and diet according to their menstrual cycle? This article describes the content of each of the presentations including the most important outcomes and conclusions drawn by the presenters.

Muscle isometric torque fluctuates according to time-of-day with such variation owed to the influence of circadian molecular clock genes. Satellite cells (SC), the muscle stem cell population, also express molecular clock genes with several contractile related genes oscillating in a diurnal pattern. Currently, limited evidence exists regarding the relationship between SCs and contractility, although long-term SC ablation alters muscle contractile function. Whether there are acute alterations in contractility following SC ablation and with respect to the time-of-day is unknown. We investigated whether short-term SC ablation affected contractile function at two times of day, and whether any such alterations lead to different extents of eccentric contraction-induced injury. Utilizing an established mouse model to deplete SCs, we characterized muscle clock gene expression and ex vivo contractility at two times-of-day (morning 0700 h and afternoon, 1500 h). Morning-SC ⁺ animals demonstrated ~25-30% reductions in tetanic/eccentric specific forces and, after eccentric injury, exhibited ~30% less force-loss and ~50% less dystrophin negative fibers versus SC ⁻ counterparts; no differences were noted between Afternoon groups (Morning-SC ⁺ : -5.63 ± 0.61, Morning-SC ⁻ : -7.93 ± 0.61; N/cm ² ; p < 0.05) (Morning-SC ⁺ : 32 ± 2.1, Morning-SC ⁻ : 64 ± 10.2; dystrophin negative fibers; p < 0.05). As Ca ⁺⁺ kinetics underpin force-generation, we also evaluated caffeine-induced contracture-force as an indirect marker of Ca ⁺⁺ availability, and found similar force reductions in Morning-SC ⁺ vs SC ⁻ mice. We conclude that force-production is reduced in the presence of SCs in the morning but not the afternoon, suggesting that SCs may have a time-of-day influence over contractile-function.

All guidelines worldwide strongly recommend exercise as a pillar of the management of patients affected by lower extremity peripheral artery disease (PAD). Exercise therapy in this setting presents different modalities, and a structured programme provides optimal results. This clinical consensus paper is intended for clinicians to promote and assist for the set-up of comprehensive exercise programmes to best advice in patients with symptomatic chronic PAD. Different exercise training protocols specific for patients with PAD are presented. Data on patient assessment and outcome measures are narratively described based on the current best evidence. The document ends by highlighting disparities in access to supervised exercise programmes across Europe and the series of gaps for evidence requiring further research.

All guidelines worldwide strongly recommend exercise as a pillar in the management of patients affected by lower extremity peripheral artery disease (PAD). Exercise therapy in this setting presents different modalities, and a structured programme provides optimal results. This clinical consensus paper is intended to promote and assist the set up of comprehensive exercise programmes and best advice for patients with symptomatic chronic PAD. Different exercise training protocols specific for patients with PAD are presented. Data on patient assessment and outcome measures are described based on the current best evidence. The document ends by highlighting supervised exercise programme access disparities across Europe and the evidence gaps requiring further research.