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Organized Sport Participation From Childhood to Adolescence Is Associated With Bone Mass in Young Adults From the Raine Study.
McVeigh, JA, Howie, EK, Zhu, K, Walsh, JP, Straker, L
Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research. 2019;(1):67-74
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Abstract
There is a critical need for longitudinal cohort studies to consider the association of the cumulative exposure of physical activity during childhood and adolescence and bone mass. The aim of this study was to investigate the relationship between organized sports trajectories (that capture distinct and potentially meaningful patterns over critical developmental periods) and bone mass at age 20 years. Participation in organized sport was recorded by parental report at ages 5, 8, 10, 14, and 17 years in 984 offspring (48% female) of a pregnancy cohort (Raine Study). Latent class analysis identified three trajectory classes in each sex. In females, these were "consistent sport participators" (48%), "dropouts" (34%), and "non-participators" (18%); in males, "consistent sport participators" (55%), "dropouts" (37%), and "sport joiners" (8%). Whole-body bone mineral content (BMC) at age 20 years was assessed by dual-energy X-ray absorptiometry (DXA). At age 20 years, after adjustment for covariates measured at age 20 years, including height, lean mass, physical activity, calcium intake, serum 25-hydroxyvitamin D, alcohol, and smoking, males who were "consistent sport participators" had significantly greater whole-body and leg BMC than those who dropped out of sport (p < 0.001), whereas males who joined sports had significantly greater leg BMC than those who dropped out of sport (p = 0.002). Females in the "consistent sport participator" trajectory had significantly greater leg BMC than those who dropped out (all p = 0.004). Participation in organized sport during childhood and adolescence is associated with bone mass at age 20 years. Because attainment of optimal peak bone mass in young adulthood is protective against osteoporosis in later life, this may have long-term skeletal benefits. © 2018 American Society for Bone and Mineral Research.
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The Prospective Association of Organized Sports Participation With Cardiovascular Disease Risk in Children (the CHAMPS Study-DK).
Hebert, JJ, Klakk, H, Møller, NC, Grøntved, A, Andersen, LB, Wedderkopp, N
Mayo Clinic proceedings. 2017;(1):57-65
Abstract
OBJECTIVE To investigate the prospective association of organized leisure-time sports participation with cardiovascular risk in children. METHODS Students were recruited from 10 public primary schools. From July 2009 to October 2010, parents reported children's weekly organized leisure-time sports participation via text messaging. Clustered cardiovascular risk was estimated with a composite score comprising fasting serum triglyceride levels, homeostasis assessment model-estimated insulin resistance, total to high-density lipoprotein cholesterol ratio, and systolic blood pressure. Additional outcomes were body mass index categories and fasting serum insulin and glucose concentrations. Associations were explored with generalized estimating equations and reported with beta coefficients (β) and percent difference per weekly sports session or incidence rate ratios. All models were adjusted for baseline values and other potential confounders. RESULTS In total, 1197 children (53% female) with a mean age of 8.4±1.4 years were included. Participating in sports for 53 weeks was associated with lower clustered cardiovascular risk (β, -0.25; 95% CI, -0.41 to -0.10; percent difference, 3.2%; 95% CI, 5.2%-1.3%). Similar outcomes were observed for log homeostasis assessment model-estimated insulin resistance (β, -0.08; 95% CI, -0.12 to -0.04; percent difference, 3.4%; 5.1%-1.7%) and log insulin (β, -0.07; 95% CI, -0.11 to -0.04; percent difference, 2.6%; 95% CI, 4.0%-1.5%). Sports participation was associated with a 20% decreased risk of overweight/obesity (incidence rate ratio, 0.78; 95% CI, 0.64-0.96). CONCLUSION Participating in organized leisure-time sports for approximately 1 year is associated with decreased clustered cardiovascular risk in children. These findings show that participating in youth sports may be an effective strategy to reduce cardiovascular risk in children.
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3.
Magnesium intake is associated with strength performance in elite basketball, handball and volleyball players.
Santos, DA, Matias, CN, Monteiro, CP, Silva, AM, Rocha, PM, Minderico, CS, Bettencourt Sardinha, L, Laires, MJ
Magnesium research. 2011;(4):215-9
Abstract
Magnesium plays significant roles in promoting strength. Surveys of athletes reveal that intake of magnesium is often below recommended levels. We aimed to understand the impact of magnesium intake on strength in elite male basketball, handball, and volleyball players. Energy and nutrient intake were assessed from seven-day diet record. Strength tests included maximal isometric trunk flexion, extension, and rotation, handgrip, squat and countermovement Abalakov jump, and maximal isokinetic knee extension and flexion peak torques. Linear regression models were performed with significance at p<0.1. Mean magnesium intake was significantly lower than the recommended daily allowance. Regression analysis indicated that magnesium was directly associated with maximal isometric trunk flexion, rotation, and handgrip, with jumping performance tests, and with all isokinetic strength variables, independent of total energy intake. The observed associations between magnesium intake and muscle strength performance may result from the important role of magnesium in energetic metabolism, transmembrane transport and muscle contraction and relaxation.
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4.
Energy turnover during 24 hours and 6 days of adventure racing.
Enqvist, JK, Mattsson, CM, Johansson, PH, Brink-Elfegoun, T, Bakkman, L, Ekblom, BT
Journal of sports sciences. 2010;(9):947-55
Abstract
Energy turnover was assessed in two conditions of mixed ultra-endurance exercise. In Study 1, energy expenditure and intake were measured in nine males in a laboratory over 24 h. In Study 2, energy expenditure was assessed in six males during an 800-km Adventure race (mean race time 152.5 h). Individual correlations between heart rate and oxygen uptake (VO(2)) were established during pre-tests when kayaking, cycling, and running. During exercise, energy expenditure was estimated from continuous heart rate recordings. Heart rate and VO(2) were measured regularly during fixed cycling work rates to correct energy expenditure for drift in oxygen pulse. Mean energy expenditure was 18,050 +/- 2,390 kcal (750 +/- 100 kcal h(-1)) and 80,000 +/- 18,000 kcal (500 +/- 100 kcal h(-1)) in Study 1 and Study 2 respectively, which is higher than previously reported. Energy intake in Study 1 was 8,450 +/- 1,160 kcal, resulting in an energy deficit of 9,590 +/- 770 kcal. Body mass decreased in Study 1 (-2.3 +/- 0.8 kg) but was unchanged in Study 2. Fat mass decreased in Study 2 (-2.3 +/- 1.5 kg). In Study 1, muscle glycogen content decreased by only 60%. Adventure racing requires a high energy expenditure, with large inter-individual variation. A large energy deficit is caused by inadequate energy intake, possibly due to suppressed appetite and gastrointestinal problems. The oxygen pulse, comparing start to 12 h of exercise and beyond, increased by 10% and 5% in Study 1 and Study 2 respectively. Hence, estimations of energy expenditure from heart rate recordings should be corrected according to this drift.
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5.
Plasma visfatin and ghrelin response to prolonged sculling in competitive male rowers.
Jürimäe, J, Rämson, R, Mäestu, J, Purge, P, Jürimäe, T, Arciero, PJ, von Duvillard, SP
Medicine and science in sports and exercise. 2009;(1):137-43
Abstract
PURPOSE The 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. METHODS Nine 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. RESULTS No 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). CONCLUSION Acute 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.
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6.
Bone mineral density in female high school athletes: interactions of menstrual function and type of mechanical loading.
Nichols, JF, Rauh, MJ, Barrack, MT, Barkai, HS
Bone. 2007;(3):371-7
Abstract
During adolescence, skeletal integrity of girls is largely dependent on menstrual function and impact exercise, yet currently there is limited research regarding the interaction between menstrual status and type of mechanical loading associated with various high school sports. Our purpose was to examine associations of menstrual status, type of mechanical loading, and bone mineral density (BMD) in female high school athletes participating in high/odd impact or repetitive/non-impact sport. Participants were 161 female high school athletes (15.7+/-1.3 years; 165.3+/-6.9 cm; 59.4+/-8.7 kg) representing high/odd impact (n=93, including soccer, softball, volleyball, tennis, lacrosse, and track sprinters and jumpers), or repetitive/non-impact sports (n=68, including swimmers, cross-country and track distance runners who participated in events>or=800 m). Areal BMD was measured by DXA at the spine (L1-L4), proximal femur, and total body. Menstrual status was determined by self-report. Athletes with primary, secondary or oligomenorrhea were combined into a single group (oligo/amenorrheic) and compared to eumenorrheic athletes. Analysis of covariance (ANCOVA) with Bonferroni post hoc comparisons adjusted for age, BMI, and gynecological age were used to compare BMD of athletes in combined mechanical loading and menstrual status groups. We found significantly greater total hip (p=0.04) and trochanter (p=0.02) BMD (g cm(-2)) among eumenorrheic high/odd impact compared to eumenorrheic repetitive/non-impact athletes, and greater spine (p=0.01) and trochanter (p=0.04) BMD among high/odd impact eumenorrheic athletes compared to repetitive/non-impact oligo/amenorrheic athletes. Chi-squared analysis of BMD Z-scores adjusted for gynecological age showed a significantly greater percentage of repetitive/non-impact athletes (33.9%) compared to high/odd impact athletes (11.8%) with low spine BMD for their age (BMD Z-score
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Effect of lycopene supplementation on lung function after exercise in young athletes who complain of exercise-induced bronchoconstriction symptoms.
Falk, B, Gorev, R, Zigel, L, Ben-Amotz, A, Neuman, I
Annals of allergy, asthma & immunology : official publication of the American College of Allergy, Asthma, & Immunology. 2005;(4):480-5
Abstract
BACKGROUND It has been suggested that exercise-induced bronchoconstriction may involve oxidative stress. Strenuous exercise promotes free radical production, which can lead to many of the pathophysiologic changes associated with asthma, including bronchoconstriction, mucus secretion, and microvascular leakage. Lycopene has been shown to have high antioxidative activity. OBJECTIVE To evaluate the effect of lycopene supplementation on airway hyperreactivity and inflammation in young athletes who complain of difficulty in breathing related to physical exertion. METHODS Nineteen young athletes with exercise-related difficulty in breathing visited the exercise laboratory 3 times. During the first visit, participants underwent a baseline evaluation of exercise-induced bronchoconstriction. Daily for 1 week before each of the 2 subsequent visits, participants ingested 30 mg of lycopene (a natural antioxidant) or placebo (in randomized order, double-blind). A 2-week washout period was given between each visit. During each visit, lung functions were evaluated before and after an 8-minute run on the treadmill (85% of the predicted maximal heart rate). RESULTS There was no difference in the mean+/-SD decrease in forced expiratory volume in 1 second after exercise during lycopene treatment compared with placebo treatment (11.8%+/-12.5% and 11.0%+/-11.6%). In addition, there was no apparent division into responders and nonresponders. CONCLUSION A daily dose of lycopene for 1 week does not affect lung function after exercise and may not provide any protective effect against clinical difficulty in breathing in young athletes.
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Influence of chronic supplementation of arginine aspartate in endurance athletes on performance and substrate metabolism - a randomized, double-blind, placebo-controlled study.
Abel, T, Knechtle, B, Perret, C, Eser, P, von Arx, P, Knecht, H
International journal of sports medicine. 2005;(5):344-9
Abstract
The intake of arginine aspartate has been shown to increase anabolic hormones like human growth hormone (hGH) and glucagon. The aim of our study was to investigate whether daily intake of two different dosages of arginine asparate during four weeks affects selected parameters of overtraining syndrome like performance, metabolic and endocrine parameters. Thirty male endurance-trained athletes were included in a randomized, double-blind, placebo-controlled study and divided into three groups. During four weeks, they ingested either arginine aspartate with a high concentration (H) of 5.7 g arginine and 8.7 g aspartate, with a low concentration (L) of 2.8 g arginine and 2.2 g aspartate or placebo (P).VO(2)peak and time to exhaustion were determined on a cycling ergometer in an incremental exercise test before and after supplementation. Before and after each incremental exercise test, concentrations of hGH, glucagon, testosterone, cortisol, ferritine, lactate, and urea were measured. Compared to placebo, no significant differences on endurance performance (VO(2)peak, time to exhaustion), endocrine (concentration of hGH, glucagon, cortisol, and testosterone) and metabolic parameters (concentration of lactate, ferritine, and urea) were found after chronic arginine aspartate supplementation. The chronic intake of arginine asparate during four weeks by male endurance athletes showed independent of dosage no influence on performance, selected metabolic or endocrine parameters. Consequently, there seems to be no apparent reason why the supplementation of arginine aspartate should be an effective ergogenic aid. The practice of using arginine aspartate as potential ergogenics should be critically reevaluated. Further investigations with higher dosage and extended supplementation periods should be performed.
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Effects of high-intensity exercises on 13C-nandrolone excretion in trained athletes.
Baume, N, Avois, L, Sottas, PE, Dvorak, J, Cauderay, M, Mangin, P, Saugy, M
Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine. 2005;(3):158-66
Abstract
OBJECTIVE Nandrolone is an anabolic steroid widely used in several sports. The numerous nandrolone positive cases in the recent years (International Olympic Committee statistics) led to several studies in the antidoping field. Nevertheless, essential questions pertaining to nandrolone endogenous production, the effects of physical exercise on the excretion of nandrolone metabolites, and contamination from nutritional supplements must still be addressed. The purpose of this study was to evaluate the influence of exhaustive exercises on 19-norandrosterone (19-NA) and 19-noretiocholanolone (19-NE) urinary excretion rates after administration of labeled nandrolone. SETTING AND PARTICIPANTS A total of 34 healthy male Caucasian volunteers from the Institute of Sports Sciences and Physical Education (University of Lausanne) applied to participate in the study. All subjects were free from any physical drug addiction and were instructed strictly to avoid any nutritional supplement or steroid before and during the study. The participants were randomly dispatched in 2 groups in a double-blind way: a placebo group and a group treated with C-labeled nandrolone. MAIN OUTCOME MEASUREMENTS The urinary concentrations of the 2 main nandrolone metabolites, 19-NA and 19-NE, were measured using gas chromatography coupled with mass spectrometry. In addition, clinical parameters such as creatinine, total protein, and beta2-microglobuline levels were determined using immunologic assays. RESULTS After an oral ingestion of a 25 mg 3,4-C2-nandrolone dose, followed by a second identical dose 24 hours later, 19-NA and 19-NE could be detected in the urine for a period of 6 days after the initial intake. Despite several interesting observations, the measurements were very scattered and did not appear to be significantly influenced by exercise sessions in the athlete population. CONCLUSIONS The results of this study suggest that physical exercise cannot be considered as a reliable parameter that systematically affects nandrolone metabolite concentrations in the urine.
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10.
Characteristics of glycemic control in elite power and endurance athletes.
Chou, SW, Lai, CH, Hsu, TH, Cho, YM, Ho, HY, Lai, YC, Chen, SM, Ho, CF, Kuo, CH
Preventive medicine. 2005;(5):564-9
Abstract
A previous study has shown that former elite power athletes exhibited significantly greater relative risk in diabetes than that of former elite endurance athletes. It is unknown whether insulin sensitivity in elite young healthy power athletes is lower than that in elite young endurance athletes. This study includes two parts, part I and part II. In the part I of this study, an oral glucose tolerance test was performed in all of the elite juvenile track athlete subjects, specializing either in short-distance racing (jSD, N = 13, aged 12.5 +/- 0.37 years) or in long-distance racing (jLD, N = 13, aged 12.6 +/- 0.42 years). In the part II of this study, we recruited elite adult swimmers and divided them into two groups according to their specialty in swimming race distance: long-distance (aLD, N = 10, age 20.3 +/- 1.32) and short-distance groups (aSD, N = 10, age 20.2 +/- 1.31). Insulin sensitivity was significantly lower in the jSD group than that in the jLD group, as indicated by the area under the curves of insulin and glucose following a 75-g oral glucose load. Fasting plasma LDL-C and total cholesterol levels in the jSD group were significantly greater than those in the jLD group. The result of the part II of this study, similar to the result of the part I, shows that insulin sensitivity in aSD swimmers was significantly lower than that in aLD swimmers. LDL-C, total cholesterol, and triglyceride levels were also found higher in aSD swimmers than in those of aLD swimmers. These new findings implicate that the genetic makeup associated with exceptional power or endurance performance of elite athletes could also reflect on their metabolic characteristics; elite power athletes appear to be more insulin resistant than elite endurance athletes.