A maximal apnoea provides significant challenges to one's physiological systems, including significantly altered arterial blood gases, and requires a highly integrative response from multiple systems, that is, changes in blood pressure, maintenance of cerebral blood flow, etc. Previous work and reviews have focused on the cardiovascular responses to a maximal apnoea, but very little work has focused upon the responses of the respiratory muscles and respiratory mechanics. This is important because of the changes to arterial blood gases leading to an increased drive to breath and the appearance of involuntary respiratory muscle contractions. This review outlines what is known about how the respiratory system responds to a maximal apnoea. We put forth the hypothesis that the respiratory muscles may become fatigued following a maximal apnoea and that the respiratory muscles of elite divers may be more fatigue‐resistant, which could be an important feature of these individuals which allows them to be successful in this sport. Finally, we provide direction for future work to explore the long‐term health of apnoea diving.

Volleyball referees, as athletes and staff members, are exposed to different stress levels which can be determined by measuring pre- and post-match levels of salivary cortisol (C) and alpha-amylase (AA). This study aimed to determine the dynamics of stress biomarkers in referees during official volleyball matches and the connection to the roles or level of competition. The participants in this study were nine international volleyball referees (three females and six males) with a mean chronological age of 48.23 ± 2.31 years. In this study, saliva samples were collected during 24 official matches during the European championship for senior women’s teams (Eurovolley 2021). The AA activity and C concentrations were determined from saliva samples. When the referees’ roles were assessed in line with their duties, the first referees’ salivary C levels showed a significant increase between the pre- and post-match measurements (p = 0.01), while in the second referees remained low. The reserve and challenge referees demonstrated a significant drop in their C concentrations (p = 0.00 and p = 0.02, respectively). Additionally, when assessing AA which accounts for the responsibilities of referees and the intensity of competition, the first (p = 0.06 and p = 0.07) and second referees (p = 0.01 and p = 0.00) showed an increase between the pre- and post-match measurements, respectively. At the same time, the AA activity did not show any significant change concerning the reserve and challenge referees. Our results indicate that referees’ roles and the level of competition may cause higher responses in “active referee roles”—mainly the first and second referees—while reserve and challenge referees showed no increase or even a decrease in the measured biomarkers. The observed changes in the stress markers can be explained by psychological or emotional effects and are dependent on the level of competition and the role referees are fulfilling.

Sport climbers should possess specific anthropometric characteristics and conditioning capacities to reach a top level in this sport. PURPOSE: The purpose of this study was to determine gender differences in the fitness status of the top-level youth sport climbers. METHODS: The study was conducted on 20 elite Croatian youth sport climbers (all members of the national team, ten females; 13-18 years of age). The variables included anthropometric status (mass, height, arm span, and body fat percentage), generic- (countermovement- and squat-jump, grip strength), and specific-fitness tests (power slap test and Draga foot lift). RESULTS: Boys were taller than girls (t-test=2.51, p=0.02, moderate effect size (ES)), and had lower body fat percentage (t=- 5.66, p=0.001, very large ES). Boys achieved better results in countermovement- (t=5.39, p=0.001, very large ES) and squat-jump (t=2.19, p=0.04, moderate ES), while there were no gender differences in the specific fitness tests. CONCLUSION: Gender differences were observed in generic but not in specific fitness, which may indicate that climbing is a specific sport that requires and develops specific abilities in a similar way in boys and girls.

Article: Forearm muscle oxygenation and blood volume parameters during sustained contraction performance in youth sport climbers - The Journal of Sports Medicine and Physical Fitness 2023 May 08 - Minerva Medica - Journals

A variety of loads are placed upon an athlete in team sports (e.g., training, match, or competitions). However, the volume of the training load plays an important role in match success. Therefore, the aim of this study was to compare the differences in biomarker dynamics during the match and during training, and to evaluate if such training represents a good stimulus for an athlete to adapt to match stress. Ten male handball players (average age of 24.1 ± 3.17 years, body height of 1.88 ± 0.64 m, and body mass of 94.6 ± 9.6 kg) took part in this study. Their saliva cortisol, testosterone, and alpha-amylase were sampled during the match and training (sessions of 90 min duration, respectively). The results showed that cortisol had higher values after the match (0.65 µg/dL) than after training (0.32 µg/dL) (p = 0.05; ES = 0.39). Testosterone concentrations had a steeper increase during a match (65%) than after training (37%). Alpha-amylase levels did not differ significantly between the match and training (p = 0.77; ES = −0.06). Overall, the results showed that the environment of a match was more stressful for the athletes; therefore, a match provoked a stronger endocrine response in the studied markers. Therefore, we concluded that a match seemed to be a stronger trigger for all of the measured biomarker responses.

Background: This study aimed to examine the difference in blood lactate and oxygen saturation between monofin swimming with respiration and with breath-hold diving. The second aim was to investigate the difference between elite and intermediate breath hold-divers. Methods: This study included 15 freediving athletes (five females). Their chronological age was 25.9 ± 2.9 years, body mass 75.5 ± 11.9 kg, and height 180.2 ± 8.9 cm. The sample of variables included anthropometric indices, blood lactate, and oxygen saturation. The participants were measured during 100 m monofin horizontal swimming with respiration and breath-hold diving. Descriptive and inferential statistics were measured. The Kolmogorov–Smirnov (K-S) test was used to determine the normality of distribution. To determine the differences between the groups of participants, the t-test was used to determine the differences in anthropometric indices. Furthermore, to observe the differences between repeated measures, ANOVA with Fischer LSD test was used. Following that, the two-factor ANOVA analysis group (respiration/apnea) and group (intermediate/elite level)) was performed to determine the possible differences between groups in both conditions. Also, Cohen’s effect size was calculated to quantify the differences among the measurements. Results: The results show that the divers perceive significantly smaller levels of lactates during dives with respiration (intermediate, 2.44 ± 0.64 mmol/L; elite, 2.23 ± 0.34 mmol/L) than during apnea (intermediate, 6.06 ± 2.00 mmol/L; elite, 4.10 ± 0.66 mmol/L). Furthermore, intermediate freedivers tend to perceive significantly higher values. Conclusions: To conclude, it can be noted that apnea monofin diving elicits significantly higher lactate production in comparison with distance-matched swimming. Such findings imply the anaerobic nature of breath-holding diving. Apart from that, elite divers tend to show a lower accumulation of lactate. Such findings imply that elite-level divers can endure prolonged apneas with lower anaerobic metabolism use.