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Biomedical subjects

J Jürimäe

Publications and source records attributed to J Jürimäe.

At least 19 recordsLinked to original sources
PubMed2006

Plasma adiponectin response to sculling exercise at individual anaerobic threshold in college level male rowers.

The purpose of the investigation was to study plasma adiponectin response to a single exercise session in male rowers. Eight college level, single scull rowers (VO2max: 5.01+/-0.43 l.min-1; age: 21.5+/-4.5 yrs; height: 184.9+/-5.0 cm; body mass: 78.5+/-8.4 kg; body fat: 11.8+/-1.2%) participated in this study. Venous blood samples were obtained before, immediately after, and following the first 30 min of recovery of constant load on-water rowing over a distance of 6.5 km (approximately 30 min) at the individual anaerobic threshold (75.2+/-2.9% of VO2max). Adiponectin was unchanged (p>0.05) immediately after the exercise. However, adiponectin was significantly increased above the resting value after the first 30 min of recovery (+14.7%; p<0.05). Similarly, leptin was unchanged immediately after exercise and was significantly decreased after the first 30 min of recovery (-18.2%; p<0.05). Plasma insulin was significantly reduced immediately after exercise and remained significantly lower during the first 30 min of recovery period. Glucose increased with exercise and returned to the pre-exercise level after the first 30 min of recovery. Basal adiponectin was significantly related to VO2max (r=-0.62; p=0.034). However, there was no relationship between basal adiponectin and other measured variables. Similarly, basal leptin demonstrated no relationship with other measured variables. In conclusion, the results of the present study suggest that plasma adiponectin is sensitive in the first 30 min of recovery to the effects of relatively short-term exercise at individual anaerobic threshold when all major muscle parts are involved.

Adiponectin↗
PubMed2006

Ghrelin response to acute aerobic exercise in boys at different stages of puberty.

The aim of this study was to investigate the changes in serum ghrelin and leptin concentrations during acute aerobic cycle ergometer test in 60 boys at different pubertal stages. Boys were divided according to their pubertal status as group I (Tanner stage 1, n=20), group II (Tanner stages 2 and 3, n=20) and group 3 (Tanner stages 4 and 5, n=20). Maximal oxygen consumption and individual ventilatory threshold of the subjects were measured directly using stepwise increasing loads on cycle ergometer. Second exercise test consisted of a 30 minute constant load exercise on the same ergometer at the level of approximately 95% of the individual ventilatory threshold. Venous blood samples were obtained before, immediately after and after 30 minutes of recovery for the measurement of serum ghrelin, leptin, testosterone and insulin. At baseline, prepubertal children had significantly higher values for serum ghrelin compared to the groups II and III. Acute exercise altered significantly only insulin concentration. In all the groups, the maximal oxygen consumption/kg correlated positively with basal levels of testosterone (r=0.60, p<0.001) and insulin (r=0.34), and negatively to ghrelin (r=-0.35) and leptin (r=-0.32) (p<0.05). We conclude that moderate acute aerobic exercise does not change serum ghrelin or leptin level in boys at different pubertal stages.

Adolescent↗
PubMed2006

Hormonal and psychological adaptation in elite male rowers during prolonged training.

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 (VO2max) was determined before and after the training period. Training was mainly organized as low-intensity prolonged training sessions. Significant increases in VO2max (from 6.2 +/- 0.5 to 6.4 +/- 0.6 l x 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.

Adaptation, Psychological↗
PubMed2006

Relationships between bone mineral density, insulin-like growth factor-1 and sex hormones in young females with different physical activity.

AIM: To study the possible relationships between bone mineral density (BMD) and blood concentrations of estradiol, progesterone and IGF-1 in strength and endurance trained and sedentary normal or overweight young females. METHODS: One hundred and twenty-nine females participated in this study and were divided into the following groups: strength trained (n=33), endurance trained (n=32), normal weight sedentary (n=42) and overweight sedentary (n=23) females. Body composition and BMD (total, dominant arm distal radius, antero-posterior lumbar spine [L2-L4] and femoral neck) values were measured using DXA. The concentrations of estradiol, progesterone and IGF-1 were measured in the blood. RESULTS: Normal weight sedentary females had lower values in BMD in sites L2-L4, femoral neck and total BMD compared to strength trained females. Overweight sedentary females had higher BMD in sites L2-L4 and total BMD compared to normal weight sedentary females. In endurance trained females, progesterone was significantly related to femoral neck BMD (r=0.76). In normal weight sedentary females, IGF-1 was significantly related to femoral neck (r =0.4) and distal radius BMD (r=0.4), and in overweight females to distal radius BMD (r=0.57). CONCLUSIONS: It was concluded that in young differently physically active females with optimal BMD, regular menstrual cycle and blood sex hormones and IGF-1, the relationship between BMD and blood biochemical parameters is not very strong. In physically inactive groups, only IGF-1 concentration influenced BMD in weight-bearing or non weight-bearing sites.

Absorptiometry, Photon↗
PubMed2005

Adiponectin is associated with bone mineral density in perimenopausal women.

The aim of the current investigation was to investigate any potential effect of fasting plasma adiponectin concentration on bone tissue, and to find possible relationships of fasting plasma adiponectin level with different body composition, insulin sensitivity and physical performance parameters in a group of healthy perimenopausal women. Twenty-one premenopausal and 17 early postmenopausal women participated in this study. The women were matched for body mass index (BMI) and level of mean daily energy expenditure. Women had similar adiponectin (8.4 +/- 3.9 vs. 9.9 +/- 5.4 microg/ml) and leptin values (12.0 +/- 7.7 vs. 14.0 +/- 8.2 ng/ml) before and after menopause. Significant relationships were observed between plasma adiponectin and bone mineral content, total bone mineral density (BMD) and lumbar spine BMD values (r > - 0.36; p < 0.05). Furthermore, adiponectin had a significant negative association with total BMD (beta = - 1.228; p = 0.004) and lumbar spine BMD (beta = - 0.312; p = 0.005) independent of the influence that other measured body compositional, hormonal or physical performance factors may exert on BMD. Adiponectin was also significantly related to waist-to-hip ratio (WHR) (beta = - 2.300; p = 0.002) and fasting insulin resistance index (FIRI) (beta = - 0.006; p = 0.007) in separate regression models. No relationship was observed between leptin and measured bone, physical performance and insulin resistance values. Leptin significantly correlated to BMI (beta = 0.018; p = 0.034), lean body mass (beta = 0.025; p = 0.024) and fat mass (beta = 0.019; p = 0.001) in separate regression models. In conclusion, the results of present study show that circulating adiponectin appears to exert an independent effect on BMD in perimenopausal women and may represent a link between adipose tissue and bone mineral density.

Adiponectin↗
PubMed2005

Leptin responses to short term exercise in college level male rowers.

OBJECTIVE: To investigate plasma leptin response to short term exercise in college level male rowers. METHODS: Thirteen rowers performed a 30 minute maximal rowing ergometer test. Venous blood samples were obtained before, immediately after, and after 30 minutes of recovery. Concentrations of leptin, insulin, growth hormone, insulin-like growth factor-I (IGF-I), and IGF binding protein-3 (IGFBP-3) were measured. RESULTS: Plasma leptin was significantly (p<0.05) decreased (from a mean (SD) of 2.7 (0.6) to 2.1 (0.8) ng/ml) and growth hormone significantly increased (from 0.6 (0.9) to 4.6 (5.4) microIU/l) immediately after the 30 minute maximal rowing exercise session (distance covered 7870.4 (443.3) m; blood lactate immediately after the test 14.9 (4.3) mmol/l). All other blood variables measured were not significantly changed as a result of the ergometer test. A positive relation was observed between the decreased plasma leptin concentration immediately after the test and the distance covered (R(2) = 0.645; p<0.05). Changes in leptin and IGF-I concentrations immediately after the test were also related (R(2) = 0.390; p<0.05). Percentage body fat explained 89.6% (p<0.05) of the variance (R(2) x 100) in basal leptin concentration. After normalisation for body fat, basal leptin was related (p<0.05) to basal insulin (r = 0.82) and training history (r = -0.60). CONCLUSION: Leptin is sensitive to relatively short term intense exercise when all major muscles are involved.

Adolescent↗
PubMed2005

Hormonal response to maximal rowing before and after heavy increase in training volume in highly trained male rowers.

AIM: The aim of this study was to investigate the hormonal response at rest and during maximal 2,000 m rowing ergometer test in 12 highly trained male rowers before and after 3 week heavy training, and after 2 week tapering periods. METHODS: Venous blood samples were obtained before, immediately after and after 30 min of recovery of the rowing performance test. Testosterone, cortisol and sex hormone binding globulin were measured, and free testosterone and the free testosterone: cortisol ratio calculated. RESULTS: Mean training time was about 100% higher during the heavy training period (17.5 h x week(-1)) compared to the tapering period (8.9 h x week(-1)). Two thousand meter rowing ergometer performance parameters were not different between 3 tests. Resting testosterone and cortisol values were not different between 3 tests. Three week heavy training period induced significant reductions in resting free testosterone and free testosterone: cortisol ratio. Resting free testosterone and free testosterone: cortisol ratio were increased to the pretraining level after 2 week tapering period. A significantly (p<0.05) lower maximal exercise-induced increase of the free testosterone level was measured after heavy training period. The response of cortisol was unchanged and free testosterone: cortisol ratio demonstrated a trend (p>0.05) for a decrease after heavy training period. CONCLUSIONS: Our findings indicate that the first sign of decreased adaptivity in athletes is a decreased resting level of free testosterone and a lower maximal exercise-induced increase in free testosterone concentration. In addition, heavy training load higher than 1,000 min per week can be sustained for 3 weeks when sufficient tapering period is followed in highly trained male rowers.

Adult↗
PubMed2004

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.

Adult↗
PubMed2004

Plasma leptin responses to prolonged sculling in female rowers.

AIM: Plasma leptin concentrations are reduced in the presence of a negative energy balance. The purpose of this study was to investigate the effects of a prolonged single endurance rowing training session on plasma leptin concentrations in female rowers. METHODS: Ten female college level single scull rowers participa-ted in this study. Venous blood samples were obtained during the early follicular phase of the menstrual cycle immediately before and after on-water rowing lasting about 2 h (7518+/-293 s; distance covered 18.9+/-1.4 km; heart rate 150+/-7 beats. min(-1)). RESULTS: Blood lactate concentration did not change significantly during sculling training session (from 1.6+/-0.4 to 1.9+/-0.5 mmol. L(-1)) indicating that training was performed at moderate intensities. Leptin values were significantly reduced immediately after prolonged rowing by a mean 44% and no further changes occurred during the first 2 h of recovery. Insulin and glucose values were also decreased immediately after prolonged rowing. A further reduction in insulin was seen during the 2(nd) hour of recovery. No further changes occurred during the first 2 h of recovery in glucose concentration. Plasma leptin concentrations immediately after (r=-0.64), and 30 min (r=-0.66) and 2 h (r=-0.64) after an endurance rowing training session were related (p<0.05) to the distance covered. No such relation was observed for other measured blood biochemical parameters. Leptin also correlated with insulin measured at different time points after endurance training (r>0.64; p<0.05). Regression analyses demonstrated a positive relationship between total body fat mass and plasma leptin (R(2)>0.70; p<0.001) regardless of sampling time in female rowers. CONCLUSION: Our findings indicate that a prolonged low-intensity rowing training session results in an energy deficit beyond the threshold that is necessary to reduce plasma leptin concentration without changing body fat mass in female rowers. It was suggested that plasma leptin could be regarded as a signal for metabolic reaction to endurance rowing training session and following recovery in female endurance athletes.

Adult↗
PubMed2004

Influence of anthropometric parameters on the body composition measured by bioelectrical impedance analysis or DXA in children.

AIM: To investigate the influence of anthropometric measures (skinfold thicknesses, girths, lengths and breadths/lengths) on (1) the whole body impedance and impedance index and (2) the body fat mass measured by means of DXA in children. METHODS: Nine skinfolds, 13 girths, eight lengths and eight breadths/lengths were measured in 26 boys and 27 girls, 11-12 y of age. The somatotype components-endomorphy, mesomorphy and ectomorphy--were assessed according to the method of Carter and Heath. Body impedance at 50 kHz was measured (Multiscan 5000, Bodystat Ltd, UK) and impedance index (height2 / impedance) was calculated. Four body components-total body fat mass and separate hands, legs and trunk fat mass--were determined using DXA. RESULTS: Skinfold thicknesses did not influence body impedance or impedance index according to stepwise multiple regression analysis. Impedance index was influenced more by the girth measures than was body impedance. The leg length measures highly influenced the impedance index (50-81%, R2 x 100). Different breadth/length parameters influenced body impedance and body impedance index (21-49%). Mesomorphy influenced body impedance only in boys (35%). Body fat mass measured by DXA was highly dependent on the measured skinfold thicknesses (59-92%). The influence of lengths and breadths/lengths on the total fat mass was significant (25-49%). Endomorphy characterized total fat mass as 86% and 52% in boys and girls, respectively. CONCLUSION: Variation in anthropometry highly determined the variance observed in impedance in children, and the girths were the best predictors of impedance. Selected skinfold thicknesses highly predicted fat mass measured by DXA for total body, trunk, arms and legs.

Absorptiometry, Photon↗
PubMed2003

Relationships between bioelectric impedance and subcutaneous adipose tissue thickness measured by LIPOMETER and skinfold calipers in children.

The aim of this study was to compare the relationships between bioelectrical impedance and thicknesses of adipose tissue measured by traditional skinfold caliper (double thickness) or a LIPOMETER device (single non-compressed thickness) in 9- to 12-year-old boys ( n=52) and girls ( n=44). In total, nine skinfolds (triceps, subscapular, biceps, iliac crest, supraspinale, abdominal, front thigh, medial calf, mid-axilla) were measured. Measurement for the thickness of subcutaneous adipose tissue layers (SAT-layers) by LIPOMETER were performed at 15 body sites (neck, triceps, biceps, upper back, front chest, lateral chest, upper abdomen, lower abdomen, lower back, hip, front thigh, lateral thigh, rear thigh, inner thigh, calf). Body bioelectrical impedance was measured with a multiple-frequency impedance device Multiscan-5000 (Bodystat, UK). Impedance at 50 kHz highly correlated with body mass ( r=-0.47 in boys, r=-0.46 in girls, r=-0.47 in total group). The relationship with body height was significant only in girls ( r=-0.42). Skinfold thicknesses measured by caliper did not correlate significantly with body impedance at 50 kHz. SAT-layers measured by LIPOMETER at triceps, front thigh, lateral thigh and rear thigh sites in boys and at the lateral thigh site in girls correlated significantly with body impedance measured at 50 kHz. Stepwise multiple regression analysis indicated that the iliac crest and front thigh skinfold thicknesses measured by caliper characterized only 5.7-12.0% of the impedance at 50 kHz in the total group ( n=96). From the measured 15 SAT-layers, the most significant was the lateral thigh layer which characterized 20.0%, 11.9% and 13.6% of the impedance at 50 kHz in boys, girls and the total group, respectively. It was concluded that the influence of subcutaneous adipose tissue on body impedance is relatively low in children. However, SAT-layers have a slightly higher influence on body impedance than skinfold thicknesses measured by caliper. The sum of skinfolds or SAT-layers did not correlate significantly with body impedance in any group.

Adipose Tissue↗
PubMed2003

Hormonal reactions during heavy training stress and following tapering in highly trained male rowers.

The purpose of this study was to determine whether fasting plasma leptin, cortisol, testosterone and growth hormone concentrations were altered with a heavy increase in training stress followed by a reduced stress in highly trained male rowers. Twelve male national standard rowers (age 20.5 +/- 3.0 years, height 187.9 +/- 6.1 cm, body mass 87.1 +/- 8.3 kg, percent body fat 10.4 +/- 3.2 %) underwent a three-week period of maximally increased training stress followed by a two-week tapering period. The fasting blood samples were obtained every week after the rest day. In addition, the maximal 2000-meter rowing ergometer performance time was assessed before and immediately after the exhaustive training period as well as after the tapering period. A 22 % increase in training stress caused a significant decrease (by 8 %) and increase (by 9 %) in leptin and testosterone, respectively. A further increase in training volume by 25 % significantly reduced leptin further by 35 %. At the same time, no changes were observed in testosterone. Growth hormone was significantly elevated only after the first week of heavy training stress compared to the pretraining level. In the first tapering week, where the physical stress was reduced by 50 %, leptin only significantly increased by 29 %. Testosterone and growth hormone were significantly reduced to almost pretraining levels by the end of the second tapering week. Leptin was further significantly increased during the second tapering week. Cortisol remained relatively constant during the whole study period. Similarly, rowing performance was not significantly changed. We conclude that leptin is more sensitive to the rapid and pronounced changes in training stress compared to measured stress hormones in athletes. In addition, fasting plasma leptin could be regarded as a key signal for metabolic adaptation to exhaustive training stress in highly trained male rowers.

Adult↗
PubMed2001

Plasma testosterone and cortisol responses to prolonged sculling in male competitive rowers.

In this study, we examined anabolic and catabolic hormone responses to a single endurance rowing training session in 12 male competitive single scull rowers. A work intensity eliciting a blood lactate concentration of 4 mmol(-1) was determined on a rowing ergometer during an endurance rowing training session lasting about 2 h (7891+/-761 s; distance covered 22.6+/-2.5 km; heart rate 136+/-7 beats x min(-1); intensity 77.4+/-3.8% of anaerobic threshold; mean +/- s). Venous blood samples were obtained before and after on-water rowing. Cortisol, testosterone and sex hormone binding globulin were measured and free testosterone and the free testosterone: cortisol ratio calculated. Blood lactate concentration did not change significantly during training (from 1.7+/-0.4 to 1.9+/-0.4 mmol x l(-1)); however, body mass was reduced (from 82.0+/-10.8 to 80.6+/-11.2 kg) and was related to the distance covered (r = -0.75). The concentrations of cortisol and testosterone did not change significantly during rowing or in the first 2 h of recovery. Free testosterone was reduced in the first 2 h of recovery, but no significant changes were observed in the free testosterone: cortisol ratio. Immediately after rowing, the concentrations of cortisol (r = 0.49) and free testosterone (r = -0.58) were related to the distance covered. Our findings indicate that a prolonged low-intensity training session results in a similar anabolic and catabolic hormone stimulus for trained rowers.

Adolescent↗
PubMed2001

Relationship between subcutaneous fatness and leptin in male athletes.

PURPOSE: Circulating leptin is low in trained subjects and closely related to body fat content. However, data are scarce as to whether differences exist in the relationship between different estimates of adiposity, metabolic parameters, and leptin in endurance- and resistance-trained male athletes. We investigated this relationship with special emphasis on subcutaneous fatness and its distribution. METHODS: 20 endurance (ET) and 17 resistance (RT) athletes recruited from different kind of sports were studied. Fat-free mass (FFM) was estimated by means of impedance and fat mass (FM) was calculated. Subcutaneous fat (SAT) and its distribution was measured by means of the optical device Lipometer at 15 body sites (SAT-layers; from 1-neck to 15-calf) on the right side of the body. Fifteen SAT-layers were summed to calculate SAT. Blood samples were obtained for determination for leptin, insulin, and glucose. Insulin resistance was calculated through the fasting insulin resistance index (FIRI; [insulin x glucose/25]). RESULTS: RT-athletes had a greater body mass and body fat content than ET-athletes, but no differences were found for leptin and metabolic parameters. In all athletes, estimates of adiposity were correlated to leptin. However, in ET-athletes FM (P < 0.05), FFM (P < 0.05), and SAT (P < 0.001) but not metabolic parameters were correlated to leptin. In RT-athletes, SAT (P < 0.0001), metabolic parameters (all P < 0.05), but not FM and FFM were in significant relationship with leptin. Stepwise regression revealed SAT as the main determinant for the variation in leptin in all athletes (adj. R(2 )= 0.52, P < 0.0001). CONCLUSION: The results suggest that estimates of adiposity and metabolic parameters are associated with leptin in a sport-specific manner. Whereas leptin might be regulated by overall subcutaneous fatness in athletes, our study does not imply a main influence of fat patterning on leptin in this group of trained subjects.

Adipose Tissue↗
PubMed2000

Circulatory response to single circuit weight and walking training sessions of similar energy cost in middle-aged overweight females.

The aim of this study was to compare circulatory responses to circuit weight (CWT) and aerobic walking training sessions of similar energy cost in middle-aged overweight females. Thirty-three middle-aged pre-menopausal females participated in the experiment. They were divided into overweight (n=18, 36.2 +/- 6.3 years, 166.3 +/- 8.0 cm, 83.5 +/- 9.7 kg, BMI 30.2 +/- 3.1 kg m-2) and non-overweight control (n=15, 34.1 +/- 6.3 years, 165.0 +/- 5.6 cm, 61.6 +/- 5.0 kg, BMI 22.7 +/- 1.5 kg m-2) groups. Individual physical working capacity (PWC) was measured using the cycle ergometer test (calculated at the level of predicted HRmax (205 - (1/2) age). A CWT session consisted of leg extension, bench press, sit-ups and leg press exercises. The subjects performed four circuits at the maximal possible speed, using a work-to-rest ratio of 60 s. Blood pressure (BP) was measured during every rest period between the exercises, and the heart rate (HR) was recorded continuously during the whole CWT programme. During the walking training session, the subjects walked as fast as possible on the indoor track. The total energy cost of the walking training session was the same as during the CWT session, approximately 270 kcal, and was controlled by a CALTRAC accelerometer. HR and BP were measured every 5 min during the walking training session. The PWC index was significantly (P<0.05) higher in the overweight group in comparison with the control females (215.4 +/- 76.1 and 187.9 +/- 42.4 W, respectively). The resting BP was normal in both groups (<140/90 mmHg). HR was between 120 and 140 beats min-1 during CWT and walking sessions. There were no differences in BP during both training sessions in overweight and control subjects. It was concluded that both CWT and walking training sessions were acceptable forms of physical activity to increase cardiovascular fitness in middle-aged overweight and normal body weight females.

Adult↗
PubMed2000

Changes in body fluids during endurance rowing training.

The aim of this study was to investigate the influence of long-lasting, extensive rowing training on body fluids in 12 experienced rowers (23.3 +/- 6.3 years, 188.7 +/- 5.9 cm, 82.0 +/- 10.8 kg, body mass index [BMI] 23.7 +/- 2.1). All rowers had a light traditional breakfast about 3 h before the training. The subjects rowed 2 h 17 min and covered 22.6 +/- 2.5 km. Before and immediately after the training session and after 30, 60, and 120 min of recovery, body fluid balance was measured using a multiple-frequency impedance device (Multiscan 5000, Bodystat Ltd., UK). Body resistance was measured at the right side of the body. Extracellular (ECW), intracellular (ICW), and total (TBW) body water were measured at 5, 200, and 50 kHz, respectively. Blood hemoglobin (Hgb) and hemotocrit (Hct) were measured, and changes in blood volume (BV), plasma volume (PV), and cell volume (CV) were measured according to Dill and Costill (1974). The body weight of the rowers decreased significantly (p < 0.05) from 82.0 +/- 10.8 kg to 80.6 +/- 11.2 kg during the endurance training. There were no significant changes in TBW immediately after the training session. Significant changes in the content of TBW occurred during the first 30 min of recovery (48.7 +/- 4.4 to 47.9 +/- 4.1; p < 0.05). The amount of ECW also decreased significantly during the first 30 min of recovery (23.3 +/- 2.0 to 22.7 +/- 1.91; p < 0.05). There were no significant changes in the balance of ECW. BV decreased during the training session by 2.5 +/- 5.2% (p < 0.05). There were significant relationships (p < 0.05) between the covered distance and the following parameters after the training session: body weight (r = -0.75), TBW (r = -0.75), and ECW (r = -0.83). Changes in the blood parameters did not correlate significantly with changes in body fluids and training volume. It was concluded that extensive rowing training significantly changed the balance of body fluids in rowers.

Adult↗
PubMed1998

Anthropometric and health-related fitness characteristics in middle-aged obese women.

The purpose of this investigation was to determine the possible relationships between anthropometrical and health-related fitness parameters in obese middle-aged women. Twenty one obese (BMI > 27 kg/m2) and 12 control (BMI < 27 kg/m2) middle-aged females (35-45 yrs) participated in this investigation. Three series of anthropometrical measurements on the right side of the body were taken according to the O-scale physique assessment system. The Heath-Carter anthropometric somatotyping method was used and the ratio of waist to hip circumferences was calculated. The body composition was measured using bioelectrical impedance method (Bodystat-500, UK). The following health-related fitness tests used were: dynamic sit-up, hand grip, sit-and-reach, single leg balance and plate tapping. Physical working capacity (PWC) was measured using single ergometer test. Obese women possessed significantly higher (p < 0.05) values for skinfold, girth and breadth measurements. While the differences in somatotype indices were not statistically significant (p > 0.05) between obese and control groups, the transformation of somatotype characteristics to the effect sizes (ESs) revealed that these differences were large (ectomorphy: ES = 1.73; endomorphy: ES = 1.64; mesomorphy: ES = 1.71). Relative aerobic fitness (VO2max/kg, calculated from PWC) and dynamic sit-up were higher (p < 0.05) in control subjects, while obese women presented significantly higher values for hand grip strength. The thicker skinfold thicknesses increased the absolute value of PWC in obese group (r = 0.39-0.57; p < 0.05). In contrast, the thinner skinfold thicknesses in suprailiac and mid-thigh significantly increased the absolute value of PWC in control women. There were only a few significant correlations between girth and breadth measures, and health-related fitness parameters. In addition, somatotype characteristics seldom influenced the results of health-related fitness tests. Stepwise multiple regression analysis demonstrated that health-related fitness test items were more dependent on the anthropometrical parameters in obese than in control women.

Adult↗