Nowadays, whole-body cryotherapy is a medical physical treatment widely used in sports medicine. Recovery from injuries (e.g., trauma, overuse) and after-season recovery are the main purposes for application. However, the most recent studies confirmed the anti-inflammatory, anti-analgesic, and anti-oxidant effects of this therapy by highlighting the underlying physiological responses. In addition to its therapeutic effects, whole-body cryotherapy has been demonstrated to be a preventive strategy against the deleterious effects of exercise-induced inflammation and soreness. Novel findings have stressed the importance of fat mass on cooling effectiveness and of the starting fitness level on the final result. Exposure to the cryotherapy somehow mimics exercise, since it affects myokines expression in an exercise-like fashion, thus opening another possible window on the therapeutic strategies for metabolic diseases such as obesity and type 2 diabetes. From a biochemical point of view, whole-body cryotherapy not always induces appreciable modifications, but the final clinical output (in terms of pain, soreness, stress, and post-exercise recovery) is very often improved compared to either the starting condition or the untreated matched group. Also, the number and the frequency of sessions that should be applied in order to obtain the best therapeutic results have been deeply investigated in the last years. In this article we reviewed the most recent literature, from 2010 until present, in order to give the most updated insight into this therapeutic strategy, whose rapidly increasing use is not always based on scientific assumptions and safety standards.

Exercise perturbs homeostasis, alters the levels of circulating mediators and hormones, and increases the demand by skeletal muscles and other vital organs for energy substrates. Exercise also affects bone and mineral metabolism, particularly calcium and phosphate, both of which are essential for muscle contraction, neuromuscular signaling, biosynthesis of adenosine triphosphate (ATP), and other energy substrates. Parathyroid hormone (PTH) is involved in the regulation of calcium and phosphate homeostasis. Understanding the effects of exercise on PTH secretion is fundamental for appreciating how the body adapts to exercise. Altered PTH metabolism underlies hyperparathyroidism and hypoparathyroidism, the complications of which affect the organs involved in calcium and phosphorous metabolism (bone and kidney) and other body systems as well. Exercise affects PTH expression and secretion by altering the circulating levels of calcium and phosphate. In turn, PTH responds directly to exercise and exercise-induced myokines. Here, we review the main concepts of the regulation of PTH expression and secretion under physiological conditions, in acute and chronic exercise, and in relation to PTH-related disorders.

Context: Tournament season can provoke overreaching syndrome in professional tennis players, which may lead to deteriorated performance. Thus, appropriate recovery methods are crucial for athletes in order to sustain high-level performance and avoid injuries. We hypothesized that whole-body cryostimulation could be applied to support the recovery process.Objective: To assess the effects of 5 days of whole-body cryostimulation combined with moderate-intensity training on immunologic, hormonal, and hematologic responses; resting metabolic rate; and tennis performance in a posttournament season.Design: Controlled laboratory study.Setting: National Olympic Sport Centre.Patients or Other Participants: Twelve high-ranking professional tennis players.Intervention(s): Participants followed a moderate-intensity training program. A subgroup was treated with the 5-day whole-body cryostimulation (−120°C) applied twice a day. The control subgroup participated in the training only.Main Outcome Measure(s): Pretreatment and posttreatment blood samples were collected and analyzed for tumor necrosis factor α, interleukin 6, testosterone, cortisol, and creatine kinase. Resting metabolic rate and performance of a tennis drill were also assessed.Results: Proinflammatory cytokine (tumor necrosis factor α) decreased and pleiotropic cytokine (interleukin 6) and cortisol increased in the group exposed to cryostimulation. In the same group, greater stroke effectiveness during the tennis drill and faster recovery were observed. Neither the training program nor cryostimulation affected resting metabolic rate.Conclusions: Professional tennis players experienced an intensified inflammatory response after the completed tournament season, which may lead to overreaching. Applying whole-body cryostimulation in conjunction with moderate-intensity training was more effective for the recovery process than the training itself. The 5-day exposure to cryostimulation twice a day ameliorated the cytokine profile, resulting in a decrease in tumor necrosis factor α and an increase in interleukin 6.

There is increasing attention to sprint interval exercise (SIE) training as a time-efficient exercise regime. Recent studies, including our own (Kujach et al., 2018), have shown that acute high-intensity intermittent exercise can improve cognitive function; however, the neurobiological mechanisms underlying the effect still remain unknown. We thus examined the effects of acute SIE on cognitive function by monitoring the peripheral levels of growth and neurotrophic factors as well as blood lactate (LA) as potential mechanisms. Thirty-six young males participated in the current study and were divided into two groups: SIE (n = 20; mean age: 21.0 ± 0.9 years) and resting control (CTR) (n = 16; mean age: 21.7 ± 1.3 years). The SIE session consisted of 5 min of warm-up exercise and six sets of 30 s of all-out cycling exercise followed by 4.5 min of rest on a cycling-ergometer. Blood samples to evaluate the changes of serum concentrations of brain-derived neurotrophic factor (BDNF), insulin-like growth factor-1 (IGF-1), vascular endothelial growth factor (VEGF), and blood LA were obtained at three time points: before, immediately after, and 60 min after each session. A Stroop task (ST) and trail making test (TMT) parts A and B were used to assess cognitive functions. Acute SIE shortened response times for both the ST and TMT A and B. Meanwhile, the peripheral levels of BDNF, IGF-1, and VEGF were significantly increased after an acute bout of SIE compared to those in CTR. In response to acute SIE, blood LA levels significantly increased and correlated with increased levels of BDNF, IGF-1, and VEGF. Furthermore, cognitive function and BDNF are found to be correlated. The current results suggest that SIE could have beneficial effects on cognitive functions with increased neuroprotective factors along with peripheral LA concentration in humans.

We investigated the aerobic and anaerobic benefits of high-intensity interval training performed at a work-to-rest ratio of 1:2 because little performance enhancement data exist based on this ratio. Recreationally active male volunteers (21 years, 184 cm, 81.5 kg) were randomly assigned to a training (interval training [IT] n = 10) or control group (n = 11). Baseline assessments were repeated after the last training session. Each participant underwent basic anthropometric assessment and performed a VO2max test on an electronically braked cycle ergometer and a 30-second Wingate test. Venous samples were acquired at the antecubital vein and subsequently processed for lactate (LA); samples were obtained at rest, and 5 and 15-minute post-Wingate test. The interval training used a cycling power output equivalent to 80% of VO2max (80% p VO2max) applied for 6 90-second bouts (each followed by 180-second rest) per session, 3 sessions per week, for 6 weeks. The control group maintained their normal routine for the 6-week period. Group × time repeated-measures analyses of variance revealed that IT improved VO2max (5.5 ml · kg(-1) · min), anaerobic threshold (3.8 ml · kg(-1) · min), work output (12.5 J · kg(-1)), glycolytic work (11.5 J · kg(-1)), mean power (0.3 W · kg), peak power (0.4 W · kg(-1)), and max power (0.4 W · kg(-1)); p < 0.05. Posttesting LA was lower on average for IT at the 5-minute mark but significantly so at the 15-minute mark. Twenty-seven minutes of cycling at 80% p VO2max applied with a work-to-rest ratio of 1:2 and spread over 3 sessions per week for 6 weeks provided sufficient stimulus to significantly improve markers of anaerobic and aerobic performance in recreationally active college-aged men. Inclusion of such a protocol into a training program may rapidly restore or improve a client's or athlete's maximal functional capacity.

Bone tissue can be seen as a physiological hub of several stimuli of different origin (e.g., dietary, endocrine, nervous, immune, skeletal muscle traction, biomechanical load). Their integration, at the bone level, results in: (i) changes in mineral and protein composition and microarchitecture and, consequently, in shape and strength; (ii) modulation of calcium and phosphorous release into the bloodstream, (iii) expression and release of hormones and mediators able to communicate the current bone status to the rest of the body. Different stimuli are able to act on either one or, as usual, more levels. Physical activity is the key stimulus for bone metabolism acting in two ways: through the biomechanical load which resolves into a direct stimulation of the segment(s) involved and through an indirect load mediated by muscle traction onto the bone, which is the main physiological stimulus for bone formation, and the endocrine stimulation which causes homeostatic adaptation. The third way, in which physical activity is able to modify bone functions, passes through the immune system. It is known that immune function is modulated by physical activity; however, two recent insights have shed new light on this modulation. The first relies on the discovery of inflammasomes, receptors/sensors of the innate immunity that regulate caspase-1 activation and are, hence, the tissue triggers of inflammation in response to infections and/or stressors. The second relies on the ability of certain tissues, and particularly skeletal muscle and adipose tissue, to synthesize and secrete mediators (namely, myokines and adipokines) able to affect, profoundly, the immune function. Physical activity is known to act on both these mechanisms and, hence, its effects on bone are also mediated by the immune system activation. Indeed, that immune system and bone are tightly connected and inflammation is pivotal in determining the bone metabolic status is well-known. The aim of this narrative review is to give a complete view of the exercise-dependent immune system-mediated effects on bone metabolism and function.