Determination of the Effects of a Series of Ten Whole-Body Cryostimulation Sessions on Physiological Responses to Exercise and Skin Temperature Behavior following Exercise in Elite Athletes

The present study investigated the effects of a series of 10 whole-body cryostimulation (WBC) sessions (3 min; -110 °C) on physiological and thermal responses to a submaximal exercise test in 17 elite athletes. Participants performed an exercise test twice at similar levels of intensity before and after a series of ten WBC sessions. Before and during the test, each participant's oxygen uptake (VO2), heart rate (HR), internal temperature (Ti), and skin temperature in selected areas of the skin were measured, and the mean arterial pressure (MAP), physiological strain index (PSI), and mean skin temperature (Tsk) were calculated. The results show that during exercise, increases in Ti and the PSI were significantly lower after the WBC sessions, and although there were no significant changes in HR or the MAP, the Tsk was significantly higher. Following exercise, an increase in skin temperature asymmetry over the lower-body muscles was detected. A series of WBC sessions induced a tendency toward a decrease in temperature asymmetry over the thigh muscles. In conclusion, a series of ten WBC sessions does not induce significant modifications in physiological variables but does influence the PSI and Ti during exercise. Moreover, a series of ten WBC sessions influences the distribution of skin temperature and the magnitude of temperature asymmetries in the early phase of recovery.

The Effect of Medium-Term Sauna-Based Heat Acclimation (MPHA) on Thermophysiological and Plasma Volume Responses to Exercise Performed under Temperate Conditions in Elite Cross-Country Skiers

The influence of a series of ten sauna baths (MPHA) on thermophysiological and selected hematological responses in 14 elite cross-country skiers to a submaximal endurance exercise test performed under thermoneutral environmental conditions was studied. Thermal and physiological variables were measured before and after the exercise test, whereas selected hematological indices were studied before, immediately after, and during recovery after a run, before (T1) and after sauna baths (T2). MPHA did not influence the baseline internal, body, and skin temperatures. There was a decrease in the resting heart rate (HR: p = 0.001) and physiological strain (PSI: p = 0.052) after MPHA and a significant effect of MPHA on systolic blood pressure (p = 0.03), hematological indices, and an exercise effect but no combined effect of treatments and exercise on the tested variables. A positive correlation was reported between PSI and total protein (%ΔTP) in T2 and a negative between plasma volume (%ΔPV) and mean red cellular volume (%ΔMCV) in T1 and T2 in response to exercise and a positive one during recovery. This may suggest that MPHA has a weak influence on body temperatures but causes a moderate decrease in PSI and modifications of plasma volume restoration in response to exercise under temperate conditions in elite athletes.

Effects of medium-term green tea extract supplementation combined with CrossFit workout on blood antioxidant status and serum brain-derived neurotrophic factor in young men: a pilot study

Background

Potential health benefits are attributed to the antioxidant properties of green tea polyphenolic compounds. The main aim of the study was to evaluate the effects of a six-week green tea extract (GTE) supplementation combined with CrossFit workout on blood antioxidant status and serum brain-derived neurotrophic factor (BDNF) in men.

Methods

Sixteen young males involved in CrossFit training were randomized into two groups supplemented with GTE or placebo for six weeks. Each participant performed an exercise test for the evaluation of maximum oxygen uptake (VO₂max) twice, i.e., before starting (1st trial) and after completing the supplementation combined with CrosFit workout (2nd trial). Venous blood samples were drawn at rest, immediately post-test and after one hour of recovery in order to estimate activities of antioxidant enzymes (superoxide dismutase [SOD], catalase [CAT], glutathione peroxidase [GPx], reduced glutathione [GR]), non-enzymatic antioxidants (reduced glutathione [GSH], uric acid [UA], total phenolics), total antioxidant capacity (FRAP), lipid peroxidation products (TBARS), and BDNF.

Results

Except for a significantly higher SOD activity and FRAP level recorded at rest and post-exercise in the 2nd trial compared to the corresponding values in the 1st trial, no significant differences were recorded among other assayed measures such as CAT, GPx, GR, GSH and BDNF. Moreover, a percentage increase in FRAP level was twice as high after six weeks’ GTE consumption than after placebo. Regardless of the trial, an increase in plasma UA concentration and a decrease in plasma total phenolics level were observed after exercise test. Plasma TBARS concentrations were significantly higher in PLA group after six weeks’ CrossFit training, while in GTE group they were slightly lower compared to the corresponding values in the 1st trial. Moreover, there was a significant inverse correlation between FRAP and TBARS in the GTE-supplemented group (r = − 0.40, p < 0.05).

Conclusions

A six weeks’ consumption of GTE had marginal effect on aerobic capacity and serum BDNF level in CrossFit-trained men, but it caused a marked increase in the blood antioxidant capacity and a moderate attenuation of the training-induced lipid peroxidation.

Effects of Six-Week Ginkgo biloba Supplementation on Aerobic Performance, Blood Pro/Antioxidant Balance, and Serum Brain-Derived Neurotrophic Factor in Physically Active Men

Extracts of Ginkgo biloba leaves, a natural source of flavonoids and polyphenolic compounds, are commonly used as therapeutic agents for the improvement of both cognitive and physiological performance. The present study was aimed to test the effects of a six-week supplementation with 160 mg/day of a standardized extract of Ginkgo biloba or a matching placebo on aerobic performance, blood antioxidant capacity, and brain-derived neurotrophic factor (BDNF) level in healthy, physically active young men, randomly allocated to two groups (n = 9 each). At baseline, as well as on the day following the treatment, the participants performed an incremental cycling test for the assessment of maximal oxygen uptake. Venous blood samples taken at rest, then immediately post-test and following 1 h of recovery, were analyzed for activities of antioxidant enzymes and plasma concentrations of non-enzymatic antioxidants, total phenolics, uric acid, lipid peroxidation products, ferric reducing ability of plasma (FRAP), and serum brain-derived neurotrophic factor (BDNF). Our results show that six weeks' supplementation with Ginkgo biloba extract in physically active young men may provide some marginal improvements in their endurance performance expressed as VO₂max and blood antioxidant capacity, as evidenced by specific biomarkers, and elicit somewhat better neuroprotection through increased exercise-induced production of BDNF.

Energy Expenditure and Lactate Concentration in Sports Dancers in a Simulated Final Round of the Standard Style Competition

To determine the energy expenditure in dancers and the nature of energy transformations which take place during a simulated final round of sports dance competition in standard style.

The study involved 6 sports dancing couples in highest dance classes (4 couples in S class, 2 couples in A class) according to WDSF (World Dance Sport Federation). There were two phases of the study. The first phase was to determine anthropometric indices, the second – to carry out a simulation of a tournament round in standard style. During a simulated final round of sports dance competition, heart rate (HR) and lactate concentration (La

The VO

The study results complement the knowledge on the intensity of dance effort and confirm that the dance effort during sports competition is one of the heavy forms of physical activity based on aerobic and anaerobic energy processes. Therefore, the periodization of dance couple training process should considerably take into account the implementation of training loads that would help building solid aerobic and anaerobic capacity.

Application of A Physiological Strain Index in Evaluating Responses to Exercise Stress - A Comparison Between Endurance and High Intensity Intermittent Trained Athletes

The study evaluated differences in response to exercise stress between endurance and high-intensity intermittent trained athletes in a thermoneutral environment using a physiological strain index (PSI). Thirty-two subjects participated in a running exercise under normal (23°C, 50% RH) conditions. The group included nine endurance trained athletes (middle-distance runners - MD), twelve high-intensity intermittent trained athletes (soccer players - HIIT) and eleven students who constituted a control group. The exercise started at a speed of 4 km·h^–1 which was increased every 3 min by 2 km·h^–1 to volitional exhaustion. The heart rate was recorded with a heart rate monitor and aural canal temperature was measured using an aural canal temperature probe. The physiological strain index (PSI) and the contribution of the circulatory and thermal components to the overall physiological strain were calculated from the heart rate and aural canal temperature. The physiological strain index differed between the study and control participants, but not between the MD and HIIT groups. The physiological strain in response to exercise stress in a thermoneutral environment was mainly determined based on the circulatory strain (MD group - 73%, HIIT group – 70%). The contribution of the circulatory and thermal components to the physiological strain did not differ significantly between the trained groups (MD and HIIT) despite important differences in morphological characteristics and training-induced systemic cardiovascular and thermoregulatory adaptations.

Changes in Endurance Performance in Young Athletes During Two Training Seasons

The aim of the study was to assess changes in endurance performance in young runners (females and males) during two training seasons. It involved 19 male and 16 female athletes aged 15-17 specializing in track-and-field middle and long distances runs. The following parameters were measured three times during the training season: maximal oxygen uptake, running economy, and the level of the second ventilatory threshold. Training volume and intensity during each season were analyzed within an 8-week period prior to the exercise tests. The volume and intensity of training at various stages of preparation in both seasons were similar. During the first year of observation, significant improvements in relative volume of maximal oxygen uptake were reported both in female and male athletes. During the second training season, it was found that running economy improved both in women and men, with no changes in maximal oxygen uptake. The same (in terms of volume and intensity) endurance training carried out with young runners during two consecutive training seasons can result in different training effects.

Endurance training and the risk of bronchial asthma in female cross-country skiers

Exercise is one of the crucial factors responsible for asthma development and exacerbation. The purpose of the present study was to assess the risk of bronchial asthma in female athletes. Spirometric evaluations and physical exercise test were performed and exhaled nitric oxide (eNO) levels were measured in 12 female elite cross-country skiers. Serum concentrations of interleukin 1 beta (IL-1β), tumor necrosis factor-alpha (TNF-α), and interleukin 6 (IL-6) were measured in all subjects before exercise, immediately after it, and after 15 min of recovery. Peak eNO values were 18.7±4.8 (ppb) and did not confirm the risk of early bronchial asthma symptoms. A graded exercise test caused significant increases in TNF-α and IL-1β concentration (p<0.05) after 15 min of recovery. A significant negative correlation was found between resting and post-exercise eNO and IL-6 levels (p<0.01). Our study did not confirm an increased risk of bronchial asthma or respiratory tract inflammatory conditions among female cross-country skiers exposed to physical exertion.

Effects of downhill and uphill exercises of equivalent submaximal intensities on selected blood cytokine levels and blood creatine kinase activity

The study was aimed at comparing the effects of concentric (CONC) and eccentric (ECC) exercises of equivalent (in terms of relative work load expressed as a percentage of VO2max) moderate intensity on selected blood cytokine levels and blood creatine kinase (CK) activity. Twenty recreationally active healthy young male volunteers were randomized between two groups that performed a single 1 h bout of CONC (uphill running) or ECC (downhill running) exercise at 60% of the respective individual VO2max. Venous blood taken 1 h before, at the end, and 24 h after the exercise was processed for plasma and analyzed for CK activity and IL-6, IL-1β and TNFα levels. There was no between-group difference in these cytokines prior to or just after the exercise, and in pre-exercise CK activity. The cytokines elevated significantly and similarly in both groups during the exercise, with no significant change in CK activity. Twenty-four hours later, CK activity and IL-6 were at pre-exercise levels in the CONC group, but showed further major increases in the ECC group, resulting in marked between-group differences in these indices. Changes in IL-1β and TNFα levels during the recovery period showed only minor differences between the study groups and produced no significant between-group difference in these cytokines. However, IL-1β level normalized in the ECC but not in the CONC group. The study suggests that moderate intensity ECC exercise compared to CONC exercise of equivalent relative work load results in considerably greater muscle damage and its related elevation in circulating IL-6, but it does not cause a major systemic inflammatory response.