Heart Rate and Body Temperature Evolution in an Interval Program of Passive Heat Acclimation at High Temperatures (100 ± 2 °C) in a Sauna.

Heat exposure provokes stress on the human body. If it remains constant, it leads to adaptations such as heat acclimation. This study aims to observe the evolution of heart rate (HR), core temperature (Tcore), and skin temperature (Tskin) in an intervallic program of exposure to extreme heat. Twenty-nine healthy male volunteers were divided into a control group (CG; n = 14) and an experimental group (EG; n = 15). EG experienced nine sessions (S) of intervallic exposure to high temperatures (100 ± 2 °C), whereas CG was exposed to ambient temperatures (22 ± 2 °C). HR, Tskin, and Tcore were monitored in S1, 4, 5, 8, and 9. An important increase in HR occurred in the S4 compared to the rest (p < 0.05) in EG. A lower HR was discovered in S8 and S9 compared to S4 and in S9 in relation to S1 (p < 0.05) in EG. EG experiences a gradual decrease in Tcore and Tskin, which was detected throughout the assessments, although it was only significant in the S8 and S9 (p < 0.05). Interval exposure to heat at 100 ± 2 °C elicits stress on the human organism, fundamentally increasing Tcore, Tskin, and FC. This recurring stress in the full program caused a drop in the thermoregulatory response as an adaptation or acclimation to heat.

Analysis of Intracellular and Extracellular Selenium Concentrations: Differences According to Training Level.

Trace mineral element concentrations are under homeostatic control. Selenium (Se) is a very important micronutrient for the antioxidant and immune system. Se metabolism could be modified due to physical training. This research aimed to analyze the extracellular (plasma, urine and serum) and intracellular (platelets and erythrocytes) concentrations of Se in athletes and to compare it with subjects with low levels of physical training. Forty young men divided into a control group (CG; n = 20; 19.25 ± 0.39 years) and a training group (TG; n = 20; 18.15 ± 0.27 years) participated in this study. The TG was formed by semi-professional soccer players. The analysis of Se was determined by inductively coupled plasma mass spectrometry. The TG obtained higher values of maximum oxygen consumption and muscle percentage (p < 0.05). The TG showed reduced absolute (p < 0.01) and relative (p < 0.05) Se concentrations in erythrocytes and platelets in comparison to CG. Trace element assessments should not be limited only to extracellular compartments as there could be deficiencies at the intracellular level.

Effects of Tetraselmis chuii Microalgae Supplementation on Anthropometric, Hormonal and Hematological Parameters in Healthy Young Men: A Double-Blind Study.

The aim of this study was to evaluate the effects of Tetraselmis chuii (TC) microalgae supplementation for sixty days on hematological, anthropometric and hormonal parameters in healthy young men. Forty-six men divided into a placebo group (PG; n = 16; 20.77 ± 2.7 years; 72.14 ± 7.18 kg; 1.76 ± 0.07 m), a group supplemented with 25 mg/day of TC (SG 25; n = 15; 20.40 ± 1.40 years; 71.28 ± 8.26 kg; 1.76 ± 0.05 m) and another group supplemented with 200 mg/day of TC (SG 200; n = 15; 20.83 ± 2.45 years; 72.30 ± 11.13 kg; 1.77 ± 0.08 m) participated in this double-blind study. PG ingested 200 mg/day of lactose powder. Participants underwent 4 assessments (baseline, month 1, month 2 and desadaptation) separated in time by an interval of thirty days. At SG 25 and SG 200, significant increases in percent muscle mass, erythropoietin, insulin-like growth factor 1, free testosterone, leukocytes, neutrophils and lymphocytes were observed (p < 0.05). Decreases in the levels of percent fat mass, platelets, hematocrit and mean corpuscular hemoglobin also occurred in these groups (p < 0.05). TC supplementation induced favorable changes on anthropometric, hematological and hormonal levels. In view of the data, it seems that the most effective dose was 25 mg/day of TC.

Effects of Twelve Sessions of High-Temperature Sauna Baths on Body Composition in Healthy Young Men.

The health benefits of sauna baths are attracting ever-increasing interest. Therefore, the purpose of this study was to evaluate the effects of 12 high-temperature (100 °C) sauna baths on body composition of 23 healthy young men, divided into a control group (CG) and a sauna group (SG). Both groups were initially evaluated by dual-energy X-ray absorptiometry (DXA), after which the SG experienced 12 sessions of sauna baths at high temperatures (100 °C). Initial measurements were carried out after the sauna sessions and after two weeks of decay in both groups. The muscle mass of the right leg (pre vs. decay: 9.50 (5.59) vs. 10.52 (5.15); p < 0.05; Δ 1.07%), bone mineral density (pre vs. post: 1.221 (0.35) vs. 1.315 (0.45); p < 0.05; Δ 7.7%) and bone mineral content (pre vs. post: 0.470 (0.21) vs. 0.499 (0.22); p < 0.05; Δ 6.17%) of the left leg increased in the SG after the sauna baths. It seems that exposure to heat at high temperatures could produce improvements in bone and muscle mass.

Copper concentration in erythrocytes, platelets, plasma, serum and urine: influence of physical training.

BACKGROUND: Physical training produces changes in the extracellular and intracellular concentrations of trace minerals elements. To our knowledge, only three compartments have been studied simultaneously. The aim of the present study was to analyze the influence of physical training on extracellular (serum, plasma and urine) and intracellular (erythrocytes and platelets) concentrations of Copper (Cu). METHODS: Forty young men participated in this study. The participants were divided into a training group (TG; n = 20; 18.15 ± 0.27 years; 68.59 ± 4.18 kg; 1.76 ± 0.04 m) and a control group (CG; n = 20; 19.25 ± 0.39 years; 73.45 ± 9.04 kg; 1.79 ± 0.06 m). The TG was formed by semi-professional soccer players from a youth category with a regular training plan of 10 h/week. All of them had been participating in high level competitions and had trained for at least 5 years. Plasma, serum, urine, erythrocyte and platelet samples of Cu were obtained and analyzed by inductively coupled plasma mass spectrometry (ICP-MS). RESULTS: The TG showed lower concentrations of Cu in erythrocytes (p < 0.05) despite similar intakes. There were no significant differences in Cu concentrations in plasma, serum, urine and platelets although the trend was similar to that observed in erythrocytes. CONCLUSIONS: The assessment of trace element concentrations should be carried out in both extracellular and intracellular compartments to obtain a proper evaluation and to identify possible deficiencies of the element. We believe that additional Cu supplementation is needed in athletes who perform physical training regularly.

Effects of Tetraselmis chuii Microalgae Supplementation on Ergospirometric, Haematological and Biochemical Parameters in Amateur Soccer Players.

This study aimed to analyse the effects of Tetraselmis chuii (TC) microalgae supplementation during thirty days on ergospirometric, haematological and biochemical parameters in amateur soccer players. Thirty-two amateur soccer players divided into a control group (CG; n = 16; 22.36 ± 1.36 years; 68.36 ± 3.53 kg) and a supplemented group (SG; n = 16; 22.23 ± 2.19 years; 69.30 ± 5.56 kg) participated in the double-blind study. SG ingested 200 mg of the TC per day, while CG ingested 200 mg per day of lactose powder. Supplementation was carried out for thirty days. The participants performed a maximal treadmill test until exhaustion. The ergospirometric values at different ventilatory thresholds and haematological values were obtained after the test. Heart rate decreased after supplementation with TC (p < 0.05). Oxygen pulse, relative and absolute maximum oxygen consumption increased in SG (pre vs. post; 19.04 ± 2.53 vs. 22.08 ± 2.25; 53.56 ± 3.26 vs. 56.74 ± 3.43; 3.72 ± 0.35 vs. 3.99 ± 0.25; p < 0.05). Haemoglobin and mean corpuscular haemoglobin increased in SG (pre vs. post; 15.12 ± 0.87 vs. 16.58 ± 0.74 p < 0.01; 28.03 ± 1.57 vs. 30.82 ± 1.21; p < 0.05). On the other hand, haematocrit and mean platelet volume decreased in SG (p < 0.05). TC supplementation elicited improvements in ergospirometric and haematological values in amateur soccer players. TC supplementation could be valuable for improving performance in amateur athletes.

Effect of a maximal exercise test on serum and urinary concentrations of magnesium, phosphorous, rubidium and strontium in athletes.

AIM: This study aims to determine the changes induced by a maximal exercise test until exhaustion on the serum and urinary concentrations of Magnesium (Mg), Phosphorous (P), Rubidium (Rb) and Strontium (Sr) in athletes (AG) and sedentary students (SG). METHODS: Fifty subjects participated in the study divided into two groups. In AG there were twenty-five male athletes and in SG there were twenty-five male sedentary students. Both groups performed an exercise test until exhaustion, starting at 8 or 10 km/h respectively, and increasing the speed at 1 km/h every 400 m. Serum and urine samples were obtained from all participants before and after the test. RESULTS: Regarding the basal status, AG showed lower values of Mg in serum (p < 0.05) and urine (p < 0.01), but higher concentrations of serum P (p < 0.05) in comparison to SG. Comparing the pre and post-test values, corrected or non-corrected for hemoconcentration in serum and for creatinine in urine, AG showed a decrease in serum Mg (p < 0.05), in serum P (p < 0.01) and in urinary Sr (p < 0.01) while an increase was observed in urinary P (p < 0.05) and in urinary Rb (p < 0.05). CONCLUSIONS: It can be concluded that a treadmill test until exhaustion leads to changes in serum and urinary concentrations of minerals in both AG and SG males. This may reflect an adaptive response of the body to overcome the physical stress and, in some cases, to avoid loss of these elements.

Influence of physical training on erythrocyte concentrations of iron, phosphorus and magnesium.

BACKGROUND: The present study aimed to determine changes occurring in the erythrocyte concentrations of Iron (Fe), Magnesium (Mg) and Phosphorous (P) of subjects with different levels of physical training living in the same area of Extremadura (Spain). METHODS: Thirty sedentary subjects (24.34 ± 3.02 years) without sports practice and a less active lifestyle, formed the control group (CG); 24 non-professional subjects (23.53 ± 1.85 years), who perform between 4 and 6 h/week of moderate sports practice without any performance objective and without following systematic training formed the group of subjects with a moderate level of training (MTG), and 22 professional cyclists (23.29 ± 2.73 years) at the beginning of their sports season, who performed more than 20 h/week of training, formed the high-level training group (HTG). Erythrocyte samples from all subjects were collected and frozen at - 80 °C until analysis. Erythrocyte analysis of Fe, Mg and P was performed by inductively coupled plasma mass spectrometry (ICP-MS). All results are expressed in µg/g Hb. RESULTS: The results showed that there were statistically significant lower concentrations of erythrocyte Fe, Mg and P in MTG and HTG than CG. All parameters (Fe, Mg and P concentrations in erythrocytes) correlated inversely with physical training. CONCLUSIONS: Physical exercise produces a decrease in erythrocyte concentrations of Fe, Mg and P. This situation could cause alterations in the performance of athletes given the importance of these elements. For this reason, we recommend an erythrocyte control at the beginning, and during the training period, to avoid harmful deficits.

Seric concentrations of copper, chromium, manganesum, nickel and selenium in aerobic, anaerobic and mixed professional sportsmen.

BACKGROUND: The aim of the present study was to determine changes in serum concentrations of trace elements Cooper (Cu), Chromiun (Cr), Manganesum (Mn), Nickel (Ni) and Selenium (Se) in high-level sportsmen. METHODS: Eighty professional athletes of different metabolic modalities, were recruited before the start of their training period. Thirty one sedentary participants of the same geographic area constituted the control group. Cu, Cr, Mn, Ni and Se analysis was performed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). RESULTS: Higher concentrations of Cr (p < 0.001), Mn (p < 0.085), and Ni (p < 0.001) were found in sportsmen in comparison to controls, inversely, Se values were lower (p < 0.001) among sportsmen. When sportsmen were classified by metabolic modalities, it was found that aerobic-anaerobic group had higher (p < 0.01) Cu concentrations than controls and the other sportsmen. The highest Cr values were found in aerobic participants. For Mn, the major levels were found in aerobic and aerobic-anaerobic groups as well (p < 0.001). The lowest Se levels were found among anaerobic sportsmen (p < 0.001). CONCLUSION: This research showed that daily, continuum physical training induced alterations in serum essential minerals concentrations, as well as that these changes can be dependent of the exercise modality practiced.