25 research outputs found
Cortisol is related to acute leukocytosis in maximal but not in hypertrophic dynamic resistance exercise
Introduction. Exercise induces immune changes that are multifactorial and include neuroendocrine factors. Acute resistance exercise is followed by marked increases in adrenaline, cortisol, growth hormone, and other factors that have immunomodulatory effects. The purpose of the present study was to investigate the relationship between leukocytosis and hormone responses to two different resistance exercises, low volume high load (gains in maximal strength, MAX) and high volume medium load (gains in muscle mass, HYP).
Methods. Using a cross-over design twelve healthy men participated in bilateral leg press exercise consisting of 5 sets of 10 RM and 15 sets of 1 RM. The inter-set rest period was 3 minutes for MAX and 2 minutes for HYP. Venous blood samples were taken at baseline, immediately after (P0) and 15 (P15) and 30 (P30) minutes after the exercise. Basic blood count was analyzed using Sysmex KX-21N (TOA Medical Electronics Co., Ltd., Kobe, Japan). Serum cortisol (COR), testosterone (TES), and growth hormone (GH) concentrations were analyzed by an immunometric chemiluminence method (Immunlite R 1000, DPC, Los Angeles, USA)
Results. Both exercises induced significant acute leukocytosis (p\u3c0.001). Leukocytosis was significantly higher after HYP (p\u3c0.01). COR and TES increased significantly after HYP (p\u3c0.01) but not in MAX. GH increased significantly (p\u3c0.05) in both exercises and stayed elevated at P30 in HYP. There was a significant negative correlation between acute leukocytosis and cortisol at P0 in MAX (R=-0.622, p=0.031) but not in HYP r=0.287 (p=0.366). Significant correlations between TES, GH and leukocytes were not observed.
Conclusions. Clearly, manipulation of the rest period and load in resistance exercise alters endocrinal as well as immunological responses. Hypertrophic resistance exercise triggered significantly stronger immunological as well as endocrinal responses. In line with the previous studies (e.g. Kraemer et al. 1996) cortisol did not correlate with leukocytes nor with leukocyte subgroups in HYP. It might be that cortisol acts as an anti-inflammatory agent in MAX, however in HYP leukocytosis appears to be related to additional physiological mechanisms e.g. muscle damage and metabolic demands, which might explain why we did not observe the same in HYP. When considering recovery from resistance exercise the immune system should be monitored in addition to hormones
Moderate energy restriction with high protein diet results in healthier outcome in women
BACKGROUND:
The present study compares two different weight reduction regimens both with a moderately high protein intake on body composition, serum hormone concentration and strength performance in non-competitive female athletes.
METHODS:
Fifteen normal weighted women involved in recreational resistance training and aerobic training were recruited for the study (age 28.5 ± 6.3 yr, height 167.0 ± 7.0 cm, body mass 66.3 ± 4.2 kg, body mass index 23.8 ± 1.8, mean ± SD). They were randomized into two groups. The 1 KG group (n = 8; energy deficit 1100 kcal/day) was supervised to reduce body weight by 1 kg per week and the 0.5 KG group (n = 7; energy deficit 550 kcal/day) by 0.5 kg per week, respectively. In both groups protein intake was kept at least 1.4 g/kg body weight/day and the weight reduction lasted four weeks. At the beginning of the study the energy need was calculated using food and training diaries. The same measurements were done before and after the 4-week weight reduction period including total body composition (DXA), serum hormone concentrations, jumping ability and strength measurements
RESULTS:
During the 4-week weight reduction period there were no changes in lean body mass and bone mass, but total body mass, fat mass and fat percentage decreased significantly in both groups. The changes were greater in the 1 KG group than in the 0.5 KG group in total body mass (p < 0.001), fat mass (p < 0.001) and fat percentage (p < 0.01). Serum testosterone concentration decreased significantly from 1.8 ± 1.0 to 1.4 ± 0.9 nmol/l (p < 0.01) in 1 KG and the change was greater in 1 KG (30%, p < 0.001) than in 0.5 KG (3%). On the other hand, SHBG increased significantly in 1 KG from 63.4 ± 17.7 to 82.4 ± 33.0 nmol/l (p < 0.05) during the weight reducing regimen. After the 4-week period there were no changes in strength performance in 0.5 KG group, however in 1 KG maximal strength in bench press decreased (p < 0.05) while endurance strength in squat and counter movement jump improved (p < 0.05)
CONCLUSION:
It is concluded that a weight reduction by 0.5 kg per week with ~1.4 g protein/kg body weight/day can be recommended to normal weighted, physically active women instead of a larger (e.g. 1 kg per week) weight reduction because the latter may lead to a catabolic state. Vertical jumping performance is improved when fat mass and body weight decrease. Thus a moderate weight reduction prior to a major event could be considered beneficial for normal built athletes in jumping events.peerReviewe
Effects of training on bone metabolism in young athletes
Purpose. This study investigated the effects of two types of training on the bone formation marker of osteocalcin and the bone resorption marker of tartrate-resistant acid phosphatase isoenzyme 5b (TRAP5b) in young track and field boys and girls.
Methods. The 14-year-old group (10 boys, 10 girls) performed first time an intensive and supervised 8-week plyometric training. In the 17-year-old group (13 athletic boys, 6 control boys, 12 athletic girls, 6 control girls), the normal many-sided track and field training lasted 6 months.
Results. Significant increases were noticed in osteocalcin (p < 0.01) both in younger boys and girls. The 20-m sprint
performance improved in girls (p < 0.01) and the countermovement jump height increased in boys (p < 0.001). Significant increases in 17-year-old boys and girls were observed after training in osteocalcin (p < 0.01), osteocalcin/TRAP5b ratio (p < 0.01 and p < 0.001), and the standing 5-jump (p < 0.05 and p < 0.01). Serum TRAP5b decreased both in boys (p < 0.05) and in girls (p < 0.01). The boys also improved the standing 5-jump (p < 0.01) and the 12-minute running test results (p < 0.05). In the combined group of all subjects, the correlation coefficient between TRAP5b and age was significant (r = –0.63, p < 0.001, n = 57). Conclusions. In practice, it is important to add plyometrics and other strength training in the training plans of young athletes, regardless of their events, to increase their bone metabolism and muscle strength.peerReviewe
A mismatch between athlete practice and current sports nutrition guidelines among elite female and male middle- and long-distance athletes
Contemporary nutrition guidelines promote a variety of periodized and time-sensitive recommendations, but current information regarding the knowledge and practice of these strategies among world-class athletes is limited. The aim of this study was to investigate this theme by implementing a questionnaire on dietary periodization practices in national/international level female (n = 27) and male (n = 21) middle- and long-distance runners/race-walkers. The questionnaire aimed to gain information on between and within-day dietary choices, as well as timing of pre- and posttraining meals and practices of training with low or high carbohydrate (CHO) availability. Data are shown as percentage (%) of all athletes, with differences in responses between subgroups (sex or event) shown as Chi-square x2 when p < .05. Nearly two-thirds of all athletes reported that they aim to eat more food on, or after, hard training days. Most athletes said they focus on adequate fueling (96%) and adequate CHO and protein (PRO) recovery (87%) around key sessions. Twenty-six percent of athletes (11% of middle vs 42% of long-distance athletes [x2 (1, n = 46) = 4.308, p = .038, phi = 0.3])) reported to undertake training in the fasted state, while 11% said they periodically restrict CHO intake, with 30% ingesting CHO during training sessions. Our findings show that elite endurance athletes appear to execute pre- and post-key session nutrition recovery recommendations. However, very few athletes deliberately undertake some contemporary dietary periodization approaches, such as training in the fasted state or periodically restricting CHO intake. This study suggests mismatches between athlete practice and current and developing sports nutrition guidelines
A Mismatch Between Athlete Practice and Current Sports Nutrition Guidelines Among Elite Female and Male Middle- and Long-Distance Athletes
Contemporary nutrition guidelines promote a variety of periodized and time-sensitive recommendations, but current information regarding the knowledge and practice of these strategies among world-class athletes is limited. The aim of this study was to investigate this theme by implementing a questionnaire on dietary periodization practices in national/international level female (n = 27) and male (n = 21) middle- and long-distance runners/race-walkers. The questionnaire aimed to gain information on between and within-day dietary choices, as well as timing of pre- and posttraining meals and practices of training with low or high carbohydrate (CHO) availability. Data are shown as percentage (%) of all athletes, with differences in responses between subgroups (sex or event) shown as Chi-square x2 when p < .05. Nearly two-thirds of all athletes reported that they aim to eat more food on, or after, hard training days. Most athletes said they focus on adequate fueling (96%) and adequate CHO and protein (PRO) recovery (87%) around key sessions. Twenty-six percent of athletes (11% of middle vs 42% of long-distance athletes [x2 (1, n = 46) = 4.308, p = .038, phi = 0.3])) reported to undertake training in the fasted state, while 11% said they periodically restrict CHO intake, with 30% ingesting CHO during training sessions. Our findings show that elite endurance athletes appear to execute pre- and post-key session nutrition recovery recommendations. However, very few athletes deliberately undertake some contemporary dietary periodization approaches, such as training in the fasted state or periodically restricting CHO intake. This study suggests mismatches between athlete practice and current and developing sports nutrition guidelines
Dietary microperiodization in elite female and male runners and race walkers during a block of high intensity precompetition training
We investigated one week of dietary microperiodization in elite female (n = 23) and male (n = 15) runners and race-walkers by examining the frequency of training sessions and recovery periods conducted with recommended carbohydrate (CHO) and protein availability. Food and training diaries were recorded in relation to HARD (intense or > 90min sessions; KEY) versus RECOVERY days (other-than KEY sessions; EASY). The targets for amount and timing of CHO and protein around KEY sessions were based on current nutrition recommendations. Relative daily energy and CHO intake was significantly (p < .05) higher in males (224 ± 26 kJ/kg/d, 7.3 ± 1.4 g/kg/d CHO) than females (204 ± 29 kJ/kg/d, 6.2 ± 1.1 g/kg/d CHO) on HARD days. However, when adjusted for trainingvolume (km), there was no sex-based difference in CHO intake daily (HARD: 0.42 ± 0.14 vs 0.39 ± 0.15 g/kg/km). Females appeared to periodize energy and protein intake with greater intakes on HARD training days (204 ± 29 vs 187 ± 35 kJ/kg/d, p = .004; 2.0 ± 0.3 vs 1.9 ± 0.3 g/ kg/d protein, p = .013), while males did not periodize intakes. Females showed a pattern of periodization of postexercise CHO for KEY vs EASY (0.9 ± 0.4 vs 0.5 ± 0.3 g/kg; p < .05) while males had higher intakes but only modest periodization (1.3 ± 0.9 vs 1.0 ± 0.4; p = .32). There was only modest evidence from femaleathletes of systematic microperiodization of eating patterns to meet contemporary sports nutrition guidelines. While this pattern of periodization was absent in males, in general they consumed more energy and CHO daily and around training sessions compared with females. Elite endurance athletes do not seem to systematically follow the most recent sports nutrition guidelines of periodized nutrition
Dietary Microperiodization in Elite Female and Male Runners and Race Walkers During a Block of High Intensity Precompetition Training
We investigated one week of dietary microperiodization in elite female (n = 23) and male (n = 15) runners and race-walkers by examining the frequency of training sessions and recovery periods conducted with recommended carbohydrate (CHO) and protein availability. Food and training diaries were recorded in relation to HARD (intense or > 90min sessions; KEY) versus RECOVERY days (other-than KEY sessions; EASY). The targets for amount and timing of CHO and protein around KEY sessions were based on current nutrition recommendations. Relative daily energy and CHO intake was significantly (p < .05) higher in males (224 ± 26 kJ/kg/d, 7.3 ± 1.4 g/kg/d CHO) than females (204 ± 29 kJ/kg/d, 6.2 ± 1.1 g/kg/d CHO) on HARD days. However, when adjusted for trainingvolume (km), there was no sex-based difference in CHO intake daily (HARD: 0.42 ± 0.14 vs 0.39 ± 0.15 g/kg/km). Females appeared to periodize energy and protein intake with greater intakes on HARD training days (204 ± 29 vs 187 ± 35 kJ/kg/d, p = .004; 2.0 ± 0.3 vs 1.9 ± 0.3 g/ kg/d protein, p = .013), while males did not periodize intakes. Females showed a pattern of periodization of postexercise CHO for KEY vs EASY (0.9 ± 0.4 vs 0.5 ± 0.3 g/kg; p < .05) while males had higher intakes but only modest periodization (1.3 ± 0.9 vs 1.0 ± 0.4; p = .32). There was only modest evidence from femaleathletes of systematic microperiodization of eating patterns to meet contemporary sports nutrition guidelines. While this pattern of periodization was absent in males, in general they consumed more energy and CHO daily and around training sessions compared with females. Elite endurance athletes do not seem to systematically follow the most recent sports nutrition guidelines of periodized nutrition
Effects of alfa-hydroxy-isocaproic acid on body composition, DOMS and performance in athletes
Abstract Background Alfa-Hydroxy-isocaproic acid (HICA) is an end product of leucine metabolism in human tissues such as muscle and connective tissue. According to the clinical and experimental studies, HICA can be considered as an anti-catabolic substance. The present study investigated the effects of HICA supplementation on body composition, delayed onset of muscle soreness (DOMS) and physical performance of athletes during a training period. Methods Fifteen healthy male soccer players (age 22.1+/-3.9 yr) volunteered for the 4-week double-blind study during an intensive training period. The subjects in the group HICA (n = 8) received 583 mg of sodium salt of HICA (corresponding 500 mg of HICA) mixed with liquid three times a day for 4 weeks, and those in the group PLACEBO (n = 7) received 650 mg of maltodextrin mixed with liquid three times a day for the same period. According to a weekly training schedule, they practiced soccer 3 - 4 times a week, had strength training 1 - 2 times a week, and had one soccer game during the study. The subjects were required to keep diaries on training, nutrition, and symptoms of DOMS. Body composition was evaluated with a dual-energy X-ray absorptiometry (DXA) before and after the 4-week period. Muscle strength and running velocity were measured with field tests. Results As compared to placebo, the HICA supplementation increased significantly body weight (p th week of the treatment (p Conclusion Already a 4-week HICA supplementation of 1.5 g a day leads to small increases in muscle mass during an intensive training period in soccer athletes.</p