Priit Purge

Adiponectin is altered after maximal exercise in highly trained male rowers

The purpose of present study was to investigate plasma adiponectin response to acute exercise in highly trained male rowers. Ten rowers performed a maximal 6,000-m rowing ergometer test [mean performance time ≈20xa0min; 1,200.8 (29.9)xa0s], and venous blood samples were obtained before, immediately after and after 30xa0min of recovery. In addition to adiponectin concentration, leptin, insulin, growth hormone and glucose values were measured. Adiponectin was not changed immediately after the exercise when uncorrected for plasma volume changes (−8.1%; P>0.05). However, adiponectin was decreased immediately after the exercise when adjusted for plasma volume changes (−11.3%; P<0.05). Adiponectin was significantly increased above the resting value after the first 30xa0min of recovery (uncorrected for plasma volume, +19.3%; corrected for plasma volume, +20.0%). No changes occurred in plasma leptin and insulin concentrations with exercise (uncorrected for plasma volume changes). While growth hormone and glucose values were significantly increased and decreased to the pre-exercise level immediately after the exercise and after the first 30xa0min of recovery, respectively (uncorrected for plasma volume changes), no differences in the responses to exercise were observed in these measured blood parameters when adjusting for plasma volume changes. There were no relationships between plasma adiponectin and other measured blood parameters before and after the exercise, nor were changes in adiponectin related to changes in other measured blood biochemical values after the exercise. These results suggest that plasma adiponectin is altered as a result of maximal acute exercise in highly trained athletes.

Changes in stress and recovery after heavy training in rowers

In this study, the effect of rapidly increased training volume on performance, recovery-stress state and stress hormones over a six-day training camp were investigated in competitive male rowers (n=21). The training regimen consisted mainly of low-intensity on-water rowing and resistance training, in total 19.6+/-3.8 hrs, corresponding to approximately 100% increase in training load. Two thousand metre rowing ergometer performance time worsened by the end of a heavy training period. The resting blood testosterone decreased and cortisol remained unchanged. The Recovery-Stress-Questionnaire for Athletes (RESTQ-Sport) revealed an increase in somatic components of stress (Fatigue, Somatic Complaints, Fitness/Injury) and a decrease in recovery factors (Success, Social Relaxation, Sleep Quality, Being in Shape, Self-Efficacy). Relationships were observed between training volume, and Fatigue (r=0.49), Somatic Complaints (r=0.50) and Sleep Quality (r=-0.58) at the end of heavy training. In addition, relationships were also observed between cortisol and Fatigue (r=0.48) at the end of heavy training as well as between changes in cortisol and changes in Fatigue (r=0.57) and Social Stress (r=0.51). In conclusion, changes in specific stress and recovery scales of the RESTQ-Sport for athletes and changes in stress hormone values indicated a state of heavy training stress and incomplete recovery at the end of a six-day heavy training period.

Relations among Heavy Training Stress, Mood State, and Performance for Male Junior Rowers

This study investigated the influence of rapidly increased training volume on performance and recovery-stress state perceived by 10 male junior rowers. The training during the 6-day period amounted to 21.5 ± 2.2 hr., which was equivalent to an average increase in training load by approximately 100% compared to their average training volume during the previous 4 wk. The time to row 2,000 m on a rowing ergometer and resting cortisol level were significantly increased after the 6-day training period. Scores on subscales of the Recovery Stress Questionnaire for Athletes significantly increased for somatic component of stress (Fatigue) and decreased factor indicating recovery (Social Relaxation) after the heavy training period. A correlation of .63 was found between increased training volume and scores on the Conflicts/Pressure subscale at the end of the heavy training period. Correlations were also found between changes in training volume with changes on subscales of Sleep Quality (r = −.64) and Burnout/Personal Accomplishment (r = −.66). Changes in resting cortisol levels as a result of heavy training stress were related to the changes in the following stress subscales: Social Stress (r = .76), Fatigue (r = .64), Disturbed Breaks (r = .65), and Fitness/Injury (r = 67). Changes in performance, perceived recovery-stress state and resting plasma cortisol level reflect increased stress due to high training. These results suggest that the Recovery Stress Questionnaire for Athletes could be used to evaluate the effects of rapidly increased training volume for male junior rowers.

Plasma ghrelin responses to acute sculling exercises in elite male rowers

The regulatory effect of ghrelin on growth hormone (GH) is limited in describing ghrelin response to acute submaximal exercise intensities in elite athletes. We investigated the effects of a single sculling exercise performed above and below the individual anaerobic threshold (IAT) on total ghrelin concentration in highly trained male rowers. Nine elite male rowers (20.1xa0±xa03.7xa0years; 190.0xa0±xa05.2xa0cm; 89.6xa0±xa04.6xa0kg; %body fat: 9.9xa0±xa02.5%) volunteered for this study. Single scull rowing was performed below and above IAT using a mean of 5xa0bpm above and below the heart rate of the IAT during graded exercise test. Ghrelin, leptin, GH, insulin, and glucose were measured before, immediately after, and after 30xa0min of recovery. Plasma ghrelin concentration did not increase significantly in either exercise but was approaching significance after 30xa0min of recovery (Pxa0=xa00.051) when the constant load sculling was performed at the intensity above the IAT. There were no changes in plasma leptin levels. GH increased significantly immediately after exercise and remained elevated during the 30xa0min of recovery in both exercise conditions, while insulin decreased significantly immediately after exercise and remained significantly lower after the 30xa0min of recovery in both exercise intensities. Baseline ghrelin was not correlated with the body composition, physical performance, or blood biochemical data. There was no significant relationship between plasma ghrelin and other blood variables immediately after the 30xa0min of recovery in both exercise tests and changes in ghrelin were not related to blood biochemical variables after the exercise tests. The acute constant load sculling exercise above or below IAT that increased GH concentrations did not significantly increase the circulating plasma ghrelin levels.

Longitudinal Development of Physical and Performance Parameters during Biological Maturation of Young Male Swimmers

The aim of the study was to examine the development of specific physical, physiological, and biomechanical parameters in 29 young male swimmers for whom measurements were made three times for two consecutive years. During the 400-m front-crawl swimming, the energy cost of swimming, and stroking parameters were assessed. Peak oxygen consumption (VO2 peak) was assessed by means of the backward-extrapolation technique recording VO2 during the first 20 sec. of recovery period after a maximal trial of 400-m distance. Swimming performance at different points of physical maturity was mainly related to the increases in body height and arm-span values from physical parameters, improvement in sport-specific VO2 peak value from physiological characteristics, and improvement in stroke indices on biomechanical parameters. In addition, biomechanical factors characterised best the 400-m swimming performance followed by physical and physiological factors during the 2-yr. study period for the young male swimmers.

Elevated Serum IL-6, IL-8, MCP-1, CRP, and IFN-γ Levels in 10- to 11-Year-Old Boys with Increased BMI

Background/Aims: Many inflammation parameters are associated with obesity, but few comparable data are found in youth. This study aims to characterize the differences in serum levels of 13 biochemical inflammatory markers between boys with increased BMI and boys with normal BMI, and examine the relationships between inflammation markers, skinfold thicknesses, and body composition. Participants/Methods: The participants were 38 boys (BMI above 85th percentile) and 38 boys (normal BMI) at the age of 10–11 years. Measurements included BMI, 9 skinfold thicknesses, waist and hip circumferences, and total body and trunk fat mass and percentage as indices of obesity, fasting insulin, glucose, and serum concentrations of IL-2, IL-4, IL-6, IL-8, IL-10, VEGF, IFN-γ, TNF-α, IL-1α, IL-1β, monocyte chemoattractant protein-1 (MCP-1), epidermal growth factor, and CRP. Results: Overweight boys (OWB) were taller and more frequently in puberty than normal-weight boys (NWB). Skinfold thicknesses and body composition parameters were higher in OWB. They had significantly higher serum IL-6, IL-8, IFN-γ, MCP-1, and CRP values compared to NWB. Conclusions: Six of 13 measured biochemical markers were significantly increased in OWB, indicating that many low-grade inflammatory processes are already involved in the development of obesity in childhood.

Plasma ghrelin is altered after maximal exercise in elite male rowers

The aim of the present investigation was to investigate plasma ghrelin response to acute maximal exercise in elite male rowers. Eight elite male rowers performed a maximal 6000-m rowing ergometer test (mean performance time: 19 mins 52 secs; 1192.1 ± 16.4 secs), and venous blood samples were obtained before, immediately after, and after 30 mins of recovery. In addition to ghrelin concentration, leptin, insulin, growth hormone, insulin-like growth factor-1 (IGF-1), testosterone, cortisol, and glucose values were measured. Ghrelin was significantly increased immediately after the exercise (+24.4%; P < 0.05) and was not significantly different than baseline after 30 mins of recovery. Leptin was significantly decreased immediately after the exercise (− 15.8%; P < 0.05) and remained significantly decreased after the first 30 mins of recovery. No changes occurred in insulin concentrations. Growth hormone, IGF-1, and testosterone values were significantly increased and decreased to the pre-exercise level immediately after the exercise and after the first 30 mins of recovery, respectively. Cortisol and glucose values were significantly increased immediately after the exercise and remained significantly increased during the first 30 mins of recovery. There were no relationships between plasma ghrelin and other measured blood parameters after the exercise, nor were changes in ghrelin related to changes in other measured blood biochemical values after the exercise. In conclusion, these results suggest that acute negative energy balance induced by specific maximal short-term exercise elicits a metabolic response with opposite changes in ghrelin and leptin concentrations in elite male athletes.

Plasma Visfatin and Ghrelin Response to Prolonged Sculling in Competitive Male Rowers

PURPOSEnThe aim of this investigation was to measure plasma visfatin and ghrelin responses to a single endurance rowing training session in male competitive single scull rowers.nnnMETHODSnNine national level male rowers (20.1 +/- 1.5 yr; 183.9 +/- 4.3 cm; 81.0 +/- 5.0 kg; 10.8 +/- 3.3% body fat) completed two trials (exercise or control) on separate days. The exercise consisted of a prolonged rowing training session lasting approximately 2 h (distance = 20.7 +/- 1.4 km; HR = 133 +/- 4 bpm; intensity = 80.2 +/- 1.6% of the HR turn point) followed by a 30-min rest. Venous blood samples were collected before and after on-water rowing. The control trial consisted of rest and blood collection similar to exercise trial.nnnRESULTSnNo differences were found at baseline values for plasma visfatin, ghrelin, and leptin for both trials. The estimated energy expenditure of the exercise trial was 1200-1500 kcal. Plasma visfatin (-10.0%; P < 0.05) and leptin (-20.0%; P < 0.05) were reduced, and ghrelin concentration was increased (+12.2%; P < 0.05) after a 30-min postexercise. No differences in plasma visfatin, ghrelin, or leptin over time were observed during control trial. There was no relationship between basal visfatin and body composition, energy balance, aerobic power, or blood biochemical data. Plasma visfatin (r = -0.76) and ghrelin (r = 0.75) measured immediately after the training session were related (P < 0.05) to the distance covered, and no relation was observed for postexercise leptin (r = -0.16; P > 0.05).nnnCONCLUSIONnAcute negative energy balance induced by a single endurance rowing training session elicited an inverse metabolic response in visfatin and ghrelin in competitive male rowers. Our results suggest that peripheral markers of negative energy balance, such as visfatin and ghrelin, may be regarded as signals for metabolic reaction to the energy cost of acute exercise. The results of our study also suggest that an energy-deficit threshold must be met for the response to occur.

Hormonal and psychological adaptation in elite male rowers during prolonged training

Abstract In this study, we examined possible hormonal and psychological changes in elite male rowers during a 24-week preparatory period. Eleven elite male rowers were tested on seven occasions over the 6-month training season. Fasting testosterone, growth hormone, cortisol, and creatine kinase activity, together with perceived recovery-stress state were evaluated after a day of rest. Maximal oxygen consumption ([Vdot]O2max) was determined before and after the training period. Training was mainly organized as low-intensity prolonged training sessions. Significant increases in [Vdot]O2max (from 6.2 ± 0.5 to 6.4 ± 0.6 l · min−1) were observed as a result of training. The overall perceived recovery-stress index did not change during the preparatory period. Standardized recovery and stress scores changed during the course of training in comparison with pre-training values. When basal hormone concentrations were compared with the first measurement, significant changes in testosterone and cortisol were observed together with changes in mean weekly training volume. Basal testosterone (r = 0.416; P = 0.010) and cortisol (r = 0.527; P = 0.001) were related to mean weekly training volume. Basal growth hormone did not change during the training. Changes in creatine kinase activity demonstrated similar pattern with changes in mean weekly training volume. The overall perceived recovery-stress index was related to testosterone, cortisol, growth hormone, and creatine kinase activity (r > 0.299; P < 0.015). Our findings indicate that testosterone and cortisol are more sensitive to changes in training volume than either growth hormone or perceived recovery-stress state in elite rowing training. Increases in these stress hormone concentrations represent a positive adaptation to current training load. Significant relationships between hormonal and perceived recovery-stress state suggest that metabolic and psychological changes should be carefully monitored to avoid a negative effect on the training status of elite rowers.

Physical Activity and Bone Mineral Accrual in Boys with Different Body Mass Parameters during Puberty: A Longitudinal Study

The aim of our longitudinal study was to investigate the relationships between physical activity and bone mass in boys with different body mass status during the years surrounding pubertal growth spurt. Two hundred and six boys entering puberty took part in this study. The subjects were divided into underweight (), normal weight (), overweight () and obese () groups at baseline according to age related categories. Whole-body DXA scans were performed at baseline, after 12 and 24 months to assess body composition (lean body mass, fat mass), and total body (TB), lumbar spine (LS) and femoral neck (FN) bone mineral density (BMD) parameters. Physical activity was measured by 7- day accelerometry. For longitudinal analysis, multilevel fixed effects regression models were constructed. Biological age, height and lean body mass had an effect for explanation of TB BMD, FN BMD and LS BMD. Moderate to vigorous physical activity (MVPA), vigorous physical activity (VPA) and sedentary time (SED) had the significant effect only on FN BMD. Being an underweight boy at the baseline indicated greater chance (p<0.01) to have lower TB BMD in the future (2 years at follow up) development, compared to normal weight (estimatesu200a=u200a−0.038), overweight (estimatesu200a=u200a−0.061) and obese boys (estimatesu200a=u200a−0.106).