Over the two last decades, whole-body cryotherapy/cryostimulation (WBC) has emerged as an exciting non-pharmacological treatment influencing inflammatory events at a cellular and physiological level, which can result in improved sleep quality, faster neuromuscular recovery after high-intensity exercise, and chronic pain relief for patients suffering different types of diseases (fibromyalgia, rheumatism, arthritis). Some evidence even suggests that WBC has benefits on mental health (depression, anxiety disorders) and cognitive functions in both adults and older adults, due to increased circulating BDNF levels. Recently, some safety concerns have been expressed by influential public health authorities (e.g., FDA, INSERM) based on reports from patients who developed adverse events upon or following WBC treatment. However, part of the data used to support these claims involved individuals whose entire body (except head) was exposed to extreme cold vaporized liquid nitrogen while standing in a narrow bathtub. Such a procedure is known as partial-body cryotherapy (PBC), and is often erroneously mistaken to be whole-body cryotherapy. Although having similarities in terms of naming and pursued aims, these two approaches are fundamentally different. The present article reviews the available literature on the main safety concerns associated with the use of true whole-body cryotherapy. English- and French-language reports of empirical studies including case reports, case series, and randomized controlled trials (RCTs) were identified through searches of PubMed, Scopus, Cochrane, and Web of Science electronic databases. Five case reports and two RCTs were included for a total of 16 documented adverse events (AEs). A critical in-depth evaluation of these AEs (type, severity, context of onset, participant’s medical background, follow-up) is proposed and used to illustrate that WBC-related safety risks are within acceptable limits and can be proactively prevented by adhering to existing recommendations, contraindications, and commonsense guidelines.

It has been consistently demonstrated that physical exercise is a cost-effective way to promote emotional well-being. However, the environment in which it takes place might amplify or mitigate this beneficial effect. The present study aimed at comparing the effects of walking in a natural or urban field setting on positive and negative affect. For this purpose, 150 students (46 female, 104 male; mean age: 20.2 years) were randomized into one of three groups: Green Walking (GW, n = 50), Urban Walking (UW, n = 50), or no-exercise (control; CTRL, n = 50). Positive and negative affect ratings were collected for each participant before and after walking (or before and after attending a class in the CTRL group). Exercise parameters (duration, intensity, weather conditions, group size) were identical in the GW and UW groups. The walking routes differed in terms of vegetation density, proximity of water, presence of traffic, and amount of asphalted surfaces. Participants in the GW and UW groups reported significant reductions in negative affect pre- to post walking. However, positive affect was increased only for participants in the GW group. This finding may have meaningful implications for mental health professionals who treat patients with significant emotional distress or mood instability. Several explanations are discussed as potential mechanisms for the more beneficial effect of Green walking, and presented as an important avenue for future research.

This study aims at modelling the aerodynamic interaction between a world-class runner and several pacers running in line, the objective being to determine the best drafting position in terms of potential speed gain and running time. Computational Fluid Dynamics calculations were performed to determine the aerodynamic drag forces exerted on the runners. Secondly, we estimated the metabolic savings for each of the runner’s positions in the pack of pacers. Finally, we estimated a potential equivalent running speed and a corresponding running time gain for each of the runner’s positions. Running second in a group of 5 runners would be the most effective drafting strategy, with a reduction of aerodynamic drag reaching 63.3%, corresponding to an improvement of 4.4% of the running economy. Furthermore, decreasing the drag forces acting on the runner would results in greater running speed. For example, a 63.3% reduction in the aerodynamic forces yields a 2.9% faster running speed (20.7 to 21.31 km/h) for an equal metabolic cost. Running in the wake of a leading runner (in a pack of five runners) over a marathon is estimated to provide a significant time saving of 3 min 28 s.