Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 36
Filtrar
1.
Atherosclerosis ; 53(3): 273-81, 1984 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6442153

RESUMO

We examined possible determinants of serum high density lipoprotein cholesterol (HDL-C) concentrations in 56 male distance runners (aged 20-56 years) by comparing runners whose HDL-C were either above or below the group median of 63 +/- 13 (+/- SD) mg/dl. HDL-C averaged 53 +/- 7 mg/dl for runners below and 73 +/- 11 mg/dl for runners above the median. Neither exercise training (miles run per week, years of running), physical characteristics (height, weight, adiposity), or dietary factors (total daily caloric intake and daily caloric intake from protein, fat, saturated fat, polyunsaturated fat, carbohydrate, and alcohol) differed between the two groups (P greater than 0.05, MANOVA). Apo A-I (P less than 0.01) was higher and triglyceride concentrations lower (P = 0.07) in the high HDL-C group. The data were also analyzed by comparing runners in the lowest and highest tertiles for HDL-C values and essentially the same results were obtained. When all runners were combined, neither training, physical characteristics nor dietary intake was significantly related to HDL-C (P greater than 0.05). Total cholesterol and apo A-I were directly related (r = 0.35 and r = 0.66, respectively, P less than 0.01) and triglycerides inversely related (r = -0.31, P less than 0.05) to HDL-C. Plasma post-heparin lipoprotein lipase activity (LPLA), hepatic triglyceride lipase activity (HTGLA), and HDL-C subfractions were measured in 22 runners.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Constituição Corporal , HDL-Colesterol/sangue , Dieta , Educação Física e Treinamento , Corrida , Adulto , Apolipoproteína A-I , Apolipoproteínas A/sangue , Ingestão de Energia , Humanos , Lipase/sangue , Lipase Lipoproteica/sangue , Lipoproteínas HDL/sangue , Masculino , Pessoa de Meia-Idade , Resistência Física , Triglicerídeos/sangue
2.
Am J Med ; 86(1B): 104-9, 1989 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-2913765

RESUMO

We evaluated maximal performance during cycle ergometry and treadmill exercise in 14 hypertensive male joggers treated with prazosin or atenolol in an unblinded, placebo-controlled, crossover design. Maximal oxygen uptake was measured during both exercise modalities; cardiac output was measured only during cycle ergometry using the acetylene rebreathing technique. Both drugs reduced resting systolic and diastolic blood pressures. Prazosin reduced total peripheral resistance during submaximal exercise but had little effect on maximal cycle and treadmill performance. Atenolol, in contrast, reduced treadmill duration, maximal oxygen uptake, and heart rate compared with placebo. Atenolol also increased stroke volume and the arterial venous oxygen difference and reduced cardiac output during cycle exercise. Both drugs produced similar reductions in exercise diastolic pressure, but exercise systolic pressure was lower only during atenolol treatment. Prazosin was better tolerated by the subjects and was preferred by 10 of the men. We conclude that both drugs effectively reduced resting blood pressure, but that atenolol decreased exercise cardiac output and may impede exercise performance in physically active hypertensive subjects.


Assuntos
Atenolol/uso terapêutico , Teste de Esforço , Hipertensão/fisiopatologia , Corrida Moderada , Prazosina/uso terapêutico , Corrida , Adulto , Idoso , Atenolol/efeitos adversos , Pressão Sanguínea/efeitos dos fármacos , Débito Cardíaco/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Humanos , Hipertensão/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio/efeitos dos fármacos , Prazosina/efeitos adversos , Resistência Vascular/efeitos dos fármacos
3.
Metabolism ; 37(6): 568-72, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3374323

RESUMO

We compared the clearance rate (K2) of plasma triglycerides (TG) following the intravenous (IV) infusion of a fat emulsion in 13 male endurance athletes (age 33 +/- 5.6 years, mean +/- SD) and 12 sedentary men (33 +/- 5.6 years). The athletes had lower fasting triglycerides (TG) (75 +/- 30.4 mg/dL v 125 +/- 52.5 mg/dL) and higher high-density lipoprotein (HDL) cholesterol concentrations (64 +/- 16.2 mg/dL v 42 +/- 9.4 mg/dL) than the sedentary subjects (P less than .01 for all). The higher HDL concentrations were due to increases in both the HDL2 and HDL3 subfractions. K2 in the athletes was 92% higher than that in the sedentary men (4.8 +/- 2.3%/min v 2.5 +/- 0.7%/min, P less than .01), but there was no difference in postheparin lipoprotein lipase activity (LPLA) between the groups (P greater than .05). K2 was positively correlated with LPLA (r = .51) and inversely related to fasting TG concentrations (r = -.73, P less than .01 for both). Furthermore, K2 was directly related to HDL (r = .75), HDL2 (r = .72), and HDL3 (r = .60) cholesterol concentrations (P less than .01 for all). These data suggest that the low TG levels in endurance athletes result at least in part from increased TG removal and that the elevated HDL concentrations of endurance athletes are related to enhanced fat clearance.


Assuntos
HDL-Colesterol/sangue , Resistência Física , Medicina Esportiva , Triglicerídeos/sangue , Adulto , Antropometria , Humanos , Masculino , Consumo de Oxigênio
4.
Metabolism ; 33(10): 943-50, 1984 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6482736

RESUMO

The interaction of exercise and diet in determining the lipid profiles of endurance athletes is poorly defined. Since active men consume more calories than sedentary individuals, we examined the effects of caloric restriction alone or in combination with exercise cessation on the serum lipid levels of men running 16 km daily. For seven days before each study, subjects consumed diets composed of 15% protein, 32% fat, and 53% carbohydrate. During ten-day experimental periods, one group (n = 10) continued running and consumed the same diet containing 3670 kcal/day, while two other groups consumed an identical diet containing 20% fewer calories and either continued (n = 16) or stopped (n = 15) exercise training. High-density lipoprotein cholesterol (HDL-C) concentrations decreased 1% to 5% in all groups during the seven-day preliminary diet. Additional reductions in total HDL-C concentrations were similar in the control and exercise cessation groups, but HDL2-C level decreased 15% during exercise cessation. During caloric restriction and continued running, in contrast, HDL-C concentration increased 8% and the HDL2-C subfraction increased 23%. There was little change in levels of apolipoprotein A-I concentrations during any of the protocols, demonstrating that changes in HDL-C are not necessarily attended by changes in the major HDL apoprotein. Low-density lipoprotein cholesterol (LDL-C) level decreased 10% to 15% in all groups during the preliminary period. Only small additional reductions occurred in men who continued running. Exercise cessation, however, was associated with a 10% increase in LDL-C level after only two days of inactivity.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Ingestão de Energia , Lipídeos/sangue , Lipoproteínas/sangue , Resistência Física , Esforço Físico , Peso Corporal , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Dieta , Heparina/farmacologia , Humanos , Lipólise , Masculino , Triglicerídeos/sangue
5.
Metabolism ; 36(2): 188-92, 1987 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3807790

RESUMO

We studied the effects of a single exercise session on lipid and lipoprotein concentrations and on postheparin plasma lipoprotein lipase (LPLA) and hepatic triglyceride hydrolase activities (HTGLA) in 11 trained (T) and ten untrained (UT) men. Subjects exercised on a bicycle ergometer at 80% of their maximal heart rate for one (UT) or two hours (T). Blood samples were drawn 24 hours before and at ten minutes and 24, 48, and 72 hours after exercise. Values were analyzed before and after adjustment for estimated changes in plasma volume (PV). High density lipoprotein cholesterol (HDL-C) increased 2 +/- 4 mg/dL in T (P less than 0.05) and 1 +/- 2 mg/dL in UT subjects beginning 48 hours after exercise. This increase was magnified by adjusting for the 5% to 8% postexercise expansion of PV. The increase in HDL in the T subjects was produced by increases in the HDL2-C subfraction (+3 +/- 4 mg/dL, P less than 0.05) whereas HDL3 increased in the UT men (+2 +/- 3 mg/dL, P less than 0.05). LPLA did not change in either subject group when estimated PV changes were ignored but increased 11% (P less than 0.05) at 24 hours after exercise when PV was considered. HTGLA was 11% below baseline in the UT men 24 to 72 hours after exercise (P less than 0.05) but showed no change in either subject group after adjustment for PV. These results demonstrate that exercise acutely increases HDL levels by raising the HDL2 subfraction in T and the HDL3 subfraction in UT men.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
HDL-Colesterol/sangue , Lipase Lipoproteica/sangue , Educação Física e Treinamento , Esforço Físico , Adulto , Colesterol/sangue , Teste de Esforço , Frequência Cardíaca , Humanos , Lipoproteínas HDL/sangue , Lipoproteínas HDL2 , Masculino , Fatores de Tempo , Triglicerídeos/sangue
6.
Metabolism ; 35(11): 999-1004, 1986 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3773728

RESUMO

We sought to determine the optimal dose of heparin for evaluating the activities of lipoprotein lipase (LPLA) and hepatic triglyceride hydrolase (HTGLA) in postheparin plasma. Nine physically active and ten sedentary men (age 30 +/- 5 yr, mean +/- SD) received 30, 50, 75, and 100 IU/kg of heparin in random order during a 2-week period. Based on all the samples, the average LPLA in the athletes was 43% higher (P less than 0.001) and HTGLA was 19% lower than in the untrained subjects (NS). The greatest LPLA was obtained after a heparin dose of 75 IU/kg, but LPLA after the three highest doses were not significantly different. There was also a dose effect on HTGLA (P less than 0.001) with greatest activities following doses of 75 and 100 IU/kg. Despite these dose effects, subjects maintained their rank order for both postheparin lipase activities regardless of the heparin dose. The only exception was for LPLA in the sedentary men probably because of lower LPLA and a smaller range of values. We also examined the effect of repeated daily injections of 75 IU/kg heparin on LPLA, HTGLA, and serum lipids. Repeated heparin administration on three consecutive days produced no significant effects on the apparent lipase activities. When all subjects were combined, HDL-cholesterol was increased over time (P less than 0.05) due to increases in both the HDL2 (P less than 0.05) and HDL3-cholesterol (NS) subfractions. Infusion of heparin or saline on three consecutive days into 18 additional men, however, had no effect on any lipid parameter.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Heparina/farmacologia , Lipase/sangue , Lipase Lipoproteica/sangue , Resistência Física , Adulto , Relação Dose-Resposta a Droga , Humanos , Lipídeos/sangue , Lipoproteínas/sangue , Masculino , Educação Física e Treinamento
7.
J Appl Physiol (1985) ; 65(2): 657-61, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3170418

RESUMO

We measured maximal O2 uptake (VO2max) during stationary cycling in 40 pregnant women [aged 29.2 +/- 3.9 (SD) yr, gestational age 25.9 +/- 3.3 wk]. Data from 30 of these women were used to develop an equation to predict the percent VO2max from submaximal heart rates. This equation and the submaximal VO2 were used to predict VO2max in the remaining 10 women. The accuracy of VO2max values estimated by this procedure was compared with values predicted by two popular methods: the Astrand nomogram and the VO2 vs. heart rate (VO2-HR) curve. VO2max values estimated by the derived equation method in the 10 validation subjects were only 3.7 +/- 12.2% higher than actual values (P greater than 0.05). The Astrand method overestimated VO2max by 9.0 +/- 19.4% (P greater than 0.05), whereas the VO2-HR curve method underestimated VO2max by only 1.6 +/- 10.3% in the same 10 subjects (P greater than 0.05). Both the Astrand and the VO2-HR curve methods correlated well with the actual values when all 40 subjects were considered (r = 0.77 and 0.85, respectively), but the VO2-HR curve method had a lower SE of prediction than the Astrand method (8.7 vs. 10.4%). In a comparison group of 10 nonpregnant sedentary women (29.9 +/- 4.5 yr), an equation relating %VO2max to HR nearly identical to that obtained in the pregnant women was found, suggesting that pregnancy does not alter this relationship. We conclude that extrapolating the VO2-HR curve to an estimated maximal HR is the most accurate method of predicting VO2max in pregnant women.


Assuntos
Consumo de Oxigênio , Esforço Físico , Gravidez/fisiologia , Adulto , Exercício Físico , Teste de Esforço , Feminino , Frequência Cardíaca , Humanos , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez
8.
J Appl Physiol (1985) ; 68(3): 1173-6, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2341342

RESUMO

We examined the effect of maternal weight gain during pregnancy on exercise performance. Ten women performed submaximal cycle (up to 60 W) and treadmill (4 km/h, up to 10% grade) exercise tests at 34 +/- 1.5 (SD) wk gestation and 7.6 +/- 1.7 wk postpartum. Postpartum subjects wearing weighted belts designed to equal their body weight during the antepartum tests performed two additional treadmill tests. Absolute O2 uptake (VO2) at the same work load was higher during pregnancy than postpartum during cycle (1.04 +/- 0.08 vs. 0.95 +/- 0.09 l/min, P = 0.014), treadmill (1.45 +/- 0.19 vs. 1.27 +/- 0.20 l/min, P = 0.0002), and weighted treadmill (1.45 +/ 0.19 vs. 1.36 +/- 0.20 l/min, P = 0.04) exercise. None of these differences remained, however, when VO2 was expressed per kilogram of body weight. Maximal VO2 (VO2max) estimated from the individual heart rate-VO2 curves was the same during and after pregnancy during cycling (1.96 +/- 0.37 to 1.98 +/- 0.39 l/min), whereas estimated VO2max increased postpartum during treadmill (2.04 +/- 0.38 to 2.21 +/- 0.36 l/min, P = 0.03) and weighted treadmill (2.04 +/- 0.38 to 2.19 +/- 0.38 l/min, P = 0.03) exercise. We conclude that increased body weight during pregnancy compared with the postpartum period accounts for 75% of the increased VO2 during submaximal weight-bearing exertion in pregnancy and contributes to reduced exercise capacity. The postpartum increase in estimated VO2max during weight-bearing exercise is the result of consistently higher antepartum heart rates during all submaximal work loads.


Assuntos
Exercício Físico/fisiologia , Gravidez/fisiologia , Aumento de Peso , Adulto , Débito Cardíaco , Feminino , Frequência Cardíaca , Humanos , Consumo de Oxigênio , Volume Sistólico
9.
J Appl Physiol (1985) ; 66(2): 949-54, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2708223

RESUMO

We examined the hemodynamic factors associated with the lower maximal O2 consumption (VO2max) in older formerly elite distance runners. Heart rate and VO2 were measured during submaximal and maximal treadmill exercise in 11 master [66 +/- 8 (SD) yr] and 11 young (32 +/- 5 yr) male runners. Cardiac output was determined using acetylene rebreathing at 30, 50, 70, and 85% VO2max. Maximal cardiac output was estimated using submaximal stroke volume and maximal heart rate. VO2max was 36% lower in master runners (45.0 +/- 6.9 vs. 70.4 +/- 8.0 ml.kg-1.min-1, P less than or equal to 0.05), because of both a lower maximal cardiac output (18.2 +/- 3.5 vs. 25.4 +/- 1.7 l.min-1) and arteriovenous O2 difference (16.6 +/- 1.6 vs. 18.7 +/- 1.4 ml O2.100 ml blood-1, P less than or equal to 0.05). Reduced maximal heart rate (154.4 +/- 17.4 vs. 185 +/- 5.8 beats.min-1) and stroke volume (117.1 +/- 16.1 vs. 137.2 +/- 8.7 ml.beat-1) contributed to the lower cardiac output in the older athletes (P less than or equal 0.05). These data indicate that VO2max is lower in master runners because of a diminished capacity to deliver and extract O2 during exercise.


Assuntos
Hemodinâmica , Consumo de Oxigênio , Corrida , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Pressão Sanguínea , Débito Cardíaco , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Volume Sistólico
10.
J Appl Physiol (1985) ; 66(1): 336-41, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2917938

RESUMO

Our purpose was to determine if pregnancy alters the cardiovascular response to exercise. Thirty-nine women [29 +/- 4 (SD) yr], performed submaximal and maximal exercise cycle ergometry during pregnancy (antepartum, AP, 26 +/- 3 wk of gestation) and postpartum (PP, 8 +/- 2 wk). Neither maximal O2 uptake (VO2max) nor maximal heart rate (HR) was different AP and PP (VO2 = 1.91 +/- 0.32 and 1.83 +/- 0.31 l/min; HR = 182 +/- 8 and 184 +/- 7 beats/min, P greater than 0.05 for both). Cardiac output (Q, acetylene rebreathing technique) averaged 2.2 to 2.8 l/min higher AP (P less than 0.01) at rest and at each exercise work load. Increases in both HR and stroke volume (SV) contributed to the elevated Q at the lower exercise work loads, whereas an increased SV was primarily responsible for the higher Q at higher levels. The slope of the Q vs. VO2 relationship was not different AP and PP (6.15 +/- 1.32 and 6.18 +/- 1.34 l/min Q/l/min VO2, P greater than 0.05). In contrast, the arteriovenous O2 difference (a-vO2 difference) was lower at each exercise work load AP, suggesting that the higher Q AP was distributed to nonexercising vascular beds. We conclude that Q is greater and a-vO2 difference is less at all levels of exercise in pregnant subjects than in the same women postpartum but that the coupling of the increase in Q to the increase in systemic O2 demand (VO2) is not different.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Ciclismo , Fenômenos Fisiológicos Cardiovasculares , Gravidez/fisiologia , Esportes , Adulto , Débito Cardíaco , Feminino , Frequência Cardíaca , Humanos , Consumo de Oxigênio , Período Pós-Parto/fisiologia , Volume Sistólico , Resistência Vascular
11.
Clin Chim Acta ; 184(3): 297-305, 1989 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-2515010

RESUMO

Plasma concentrations of serum amyloid A (SAA), high density lipoprotein (HDL) cholesterol, non-HDL cholesterol, and apolipoproteins (Apo) A-I and B were measured daily for 6 days in 10 patients following myocardial infarction (MI) and in 10 secular controls admitted to a coronary care unit. SAA concentrations peaked 3 days following MI (mean 47 mg/dl) and correlated with creatine kinase (CK) (r = 0.67, P less than 0.001). Non-HDL cholesterol and Apo B fell 15 and 18%, respectively, reached nadirs 3-4 days after MI and were inversely related to CK concentrations (P less than 0.01 for both). HDL cholesterol levels, in contrast, increased 15% and were significantly higher than baseline by day 3 when SAA concentrations were maximum. HDL cholesterol subsequently fell in parallel with SAA and had returned to baseline by day 6. Apo A-I declined throughout the 6 days of observation and was 13% lower than initial values on day 6 (P less than 0.05). The Apo A-I reduction was inversely related to both CK and SAA concentrations. There were no significant changes in any of the analytes in control subjects. We conclude that Apo A-I and possibly Apo B containing lipoproteins are negative acute phase reactants. HDL cholesterol is transiently elevated after MI despite decreasing Apo A-I levels and this may relate to incorporation of SAA into HDL particles.


Assuntos
Infarto do Miocárdio/sangue , Proteína Amiloide A Sérica/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Apolipoproteína A-I , Apolipoproteínas A/sangue , Apolipoproteínas B/sangue , Colesterol/sangue , HDL-Colesterol/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
12.
Sports Med ; 7(6): 357-75, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2662323

RESUMO

Alterations in maternal physiology during pregnancy affect the physiological respect to aerobic exercise. Maternal resting oxygen consumption (VO2) and cardiac output increase during pregnancy. Heart rate (HR) becomes progressively elevated through gestation, whereas stroke volume (SV) increases until the third trimester and then declines until term, probably because of diminished venous return. Plasma volume increases earlier and to a greater magnitude than red cell volume, resulting in the 'haemodilutional anaemia' of pregnancy and a decline in the oxygen-carrying capacity. Ventilation is greater during pregnancy because of elevated tidal volume and unchanged rate of breathing. The acute and chronic (training) responses to aerobic exercise during pregnancy have not been thoroughly investigated. Specifically, the effect of gestational age, maternal activity status, and type, duration and intensity of exercise on maternal cardiovascular response have only recently begun to be explored. During pregnancy cardiac output during submaximal exertion increases above values in non-pregnant women, except perhaps late in gestation. Both heart rate and stroke volume contribute to the elevated cardiac output. Changes in submaximal exercise VO2 during pregnancy are dependent on the mode of exercise. At the same workload, VO2 increases during weight-bearing exercise, but usually does not differ from postpartum values during weight-supported exercise. One study found no change in VO2max during pregnancy compared to postpartum values. Some recent evidence indicates that the cardiac output vs VO2 relationship for pregnant women is within the range of average values reported for non-pregnant individuals. Exercise arterial-venous oxygen difference is lower during pregnancy, suggesting that the higher cardiac output is distributed to non-exercising vascular beds. The data are limited but suggest that the perfusion of exercising muscle is unchanged during pregnancy and that the major haemodynamic change is an augmented cardiac output so that blood flow to the uterus and fetus is not compromised. Only one study has measured blood flow during exercise in pregnant women. The reported 25% decrease in uterine blood flow during supine cycle exercise in women late in gestation must be interpreted cautiously because the uterus may obstruct the vena cava in the supine position. Studies of exercising pregnant animals usually indicate a decreased uterine blood flow but an enhanced oxygen extraction; the lower blood flow may be limited to non-placental areas. The applicability of these results to humans is unknown.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Exercício Físico , Gravidez , Feminino , Humanos , Resultado da Gravidez
13.
Med Sci Sports Exerc ; 16(1): 72-6, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6708783

RESUMO

The present study compared the physiological responses to exercise, the anaerobic fitness, and the body composition of high-ability prepubescent wrestlers and normally active boys. The wrestlers (N = 15, mean age +/- S.D. = 11.3 +/- 0.30 yr) were recruited to participate in a summer wrestling camp. Their wrestling experience averaged 3.0 +/- 1.63 yr, during which time they won 78 +/- 10.5% of the matches. The comparison boys (N = 13, 10.7 +/- 0.36 yr) were volunteers from a local Boy's Club. Each subject performed a graded treadmill exercise test (Bruce protocol) and an anaerobic cycle ergometer test. Additionally, body composition was assessed using densitometry and skinfolds. There were no differences (P greater than 0.05) between the wrestlers and the comparison subjects for age or height. The wrestlers exercised for 1.5 min longer on the treadmill and obtained a higher VO2max (54.0 +/- 1.15 ml X min-1 X kg-1, P less than 0.05) than the comparison subjects (45.6 +/- 2.10 ml X min-1 X kg-1). Also, the wrestlers had higher anaerobic test scores, greater body densities, and lower subcutaneous fat totals at all sites than the normally active boys. These data indicate that the favorable fitness and body composition scores found previously for more mature wrestlers are already present in prepubescent wrestlers.


Assuntos
Esportes , Luta Romana , Tecido Adiposo/anatomia & histologia , Anaerobiose , Composição Corporal , Criança , Teste de Esforço , Humanos , Masculino , Consumo de Oxigênio , Aptidão Física
14.
Med Sci Sports Exerc ; 14(3): 244-8, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-7109894

RESUMO

Body composition and physical dimensions were compared between 23 young, experienced wrestlers (mean age +/- SE = 11.0 +/- 0.21 yr) and 23 school children (11.2 +/- 0.24 yr). The wrestlers were among the best wrestlers from local wrestling clubs and averaged 2.7 (+/- 0.27) yr of experience. They had won 72% (+/- 1.8%) of the total 75 (+/- 9.1) matches. The comparison group consisted of volunteers from local elementary schools. Standard densitometric and anthropometric techniques were used to measure the body composition and physical dimensions of each group. The wrestlers were 4 kg lighter (P less than 0.05) and had a smaller percent fat than the comparison group (13.3 +/- 0.66% and 20.0 +/- 1.13%, respectively). The weight difference between groups was due to the larger fat weight of the comparison group since lean weight differed by only 0.8 kg. Fat differences were also reflected in the larger skinfolds and "fat" circumferences of the comparison group. No group differences were noted in diameters. It is concluded that compared to other children young experienced wrestlers have similar skeletal structures and lean body weights. The comparison group possessed more body fat.


Assuntos
Antropometria , Composição Corporal , Esportes , Luta Romana , Tecido Adiposo/anatomia & histologia , Estatura , Peso Corporal , Criança , Humanos , Masculino , Dobras Cutâneas
15.
Med Sci Sports Exerc ; 18(4): 420-4, 1986 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3747802

RESUMO

We measured maximum oxygen uptake, estimated changes in plasma volume, and the cardiac dimensions of 15 male competitive distance runners (28.2 +/- 5.6 yr of age, mean +/- SD) before and after 10 days of exercise cessation. Subjects were habitually active but adjusted their training to run 16 km daily for 2 wk before the study. Subjects were maintained on defined diets for the week before and during the detraining period. Average body weight decreased 1.0 +/- 0.5 kg (P less than 0.001) within 2 days of exercise cessation and was accompanied by a 5.0 +/- 5.9% (P less than 0.01) decrease in estimated plasma volume. No additional changes in body weight and plasma volume occurred during the study, and estimated percent body fat did not change. Resting heart rate, blood pressure, and cardiac dimensions were also unchanged with physical inactivity. In addition, maximum oxygen uptake was not altered although peak exercise heart rate was an average of 9 +/- 5 beats X min-1 (P less than 0.01) or 5% higher after detraining. We conclude that short periods of exercise cessation decrease estimated plasma volume and increase the maximum exercise heart rate of endurance athletes but do not alter their cardiac dimensions or maximum oxygen uptake.


Assuntos
Coração/anatomia & histologia , Consumo de Oxigênio , Esforço Físico , Adaptação Fisiológica , Adulto , Peso Corporal , Coração/fisiologia , Frequência Cardíaca , Humanos , Masculino , Volume Plasmático , Corrida
16.
Med Sci Sports Exerc ; 17(4): 462-5, 1985 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-4033402

RESUMO

We quantified serum lipids and postheparin plasma lipolytic activities in 5 weightlifters presently self-administering androgenic steroids (users) and an equal number not currently using these drugs (non-users). Mean (+/- SD) age (23 +/- 2 vs 25 +/- 4 yr), body weight (102.7 +/- 11.4 vs 86.8 +/- 13.6 kg), and percent body fat (8.6 +/- 2.5 vs 7.8 +/- 6.0%) were not different in users and non-users, respectively. Similarly, there were no differences in total cholesterol (183 +/- 27 vs 176 +/- 32 mg.dl-1) low-density lipoprotein-cholesterol (138 +/- 25 vs 108 +/- 32 mg.dl-1), or triglyceride (93 +/- 26 vs 93 +/- 41 mg.dl-1) levels in the two groups. High-density lipoprotein (HDL)-cholesterol concentrations, however, were significantly lower in the users (26 +/- 10 vs 50 +/- 13 mg.dl-1; P less than 0.05), and most of the difference was due to lower HDL2-cholesterol concentrations (6 +/- 4 vs 22 +/- 9 mg.dl-1; P less than 0.05). Postheparin plasma lipoprotein lipase activity was only slightly lower in the users (3.49 +/- 2.23 vs 5.36 +/- 1.73 mumol FFA.ml-hr-1; P= NS). but hepatic triglyceride lipase activity was significantly higher in this group (27.99 +/- 6.89 vs 11.15 +/- 2.76, mumol FFA.ml-hr-1: P less than 0.001) and correlated inversely with HDL2-cholesterol concentrations (r = -0.81; P less than 0.01). We conclude that androgenic hormones reduce HDL-cholesterol concentrations and the HDL2-cholesterol subfraction, possibly by enhancing hepatic triglyceride lipase activity.


Assuntos
Anabolizantes/farmacologia , HDL-Colesterol/sangue , Lipase/metabolismo , Lipoproteínas HDL/sangue , Fígado/enzimologia , Esportes , Levantamento de Peso , Adulto , Humanos , Lipase Lipoproteica/metabolismo , Lipoproteínas HDL2 , Lipoproteínas HDL3 , Masculino
17.
Med Sci Sports Exerc ; 18(2): 197-204, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3702647

RESUMO

The effects of 10 wk of exercise training at low (40% VO2max) or high (75% VO2max) intensity on serum lipids and lipoproteins were compared in prepubescent boys and adult men. The final sample size consisted of: 8 boys (mean +/- SE age = 8.5 +/- 1.96 yr) and 8 men (36.6 +/- 3.18 yr) in low; 12 boys (8.0 +/- 1.40 yr) and 12 men (36.6 +/- 4.09 yr) in high; and 10 boys (9.0 +/- 2.08 yr) and 10 men (36.7 +/- 4.82 yr) in control. Training involved walking/jogging/running 3 d X wk-1 at a distance which progressed from 2.4 km X d-1 in the first week to 4.8 km X d-1 from the fifth week. Fasting blood samples, collected on 2 d during both pre- and post-training, were assayed for triglycerides, total cholesterol (CHOL), and high density lipoprotein cholesterol (HDL-C). Maximum aerobic power (VO2max) was determined from a treadmill test. Additionally, dietary intake was assessed from a 3-d dietary record and body composition from the sum of 6 skinfolds. The only statistically significant (P less than 0.05) changes occurred in HDL-C and CHOL for the high groups. HDL-C decreased following training. CHOL was lower for high than the other groups for the first day post-training only. There were no differences in the changes in HDL-C/CHOL ratio among the groups. VO2max only increased in the high groups. Dietary intake and body weight did not change. Further statistical adjustment in lipids for changes in sum of 6 skinfolds did not alter the results.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Lipídeos/sangue , Educação Física e Treinamento , Adulto , Fatores Etários , Composição Corporal , Criança , Colesterol/sangue , HDL-Colesterol/sangue , Dieta , Humanos , Masculino , Consumo de Oxigênio , Aptidão Física
18.
Clin Sports Med ; 5(3): 493-514, 1986 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3521898

RESUMO

Definitive statements concerning the cardiorespiratory effects of exercise training in children cannot be made. Few carefully controlled and well-defined exercise training studies including important cardiorespiratory variables have been conducted. Generally, it appears that the response to training in pubescent and postpubescent children is not different from what is observed in adults.


Assuntos
Fenômenos Fisiológicos Cardiovasculares , Educação Física e Treinamento , Fenômenos Fisiológicos Respiratórios , Adolescente , Adulto , Fatores Etários , Débito Cardíaco , Criança , Pré-Escolar , Doença das Coronárias/etiologia , Feminino , Frequência Cardíaca , Humanos , Estudos Longitudinais , Masculino , Consumo de Oxigênio , Projetos de Pesquisa , Fatores de Tempo
19.
Phys Sportsmed ; 18(9): 106-15, 1990 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27447589

RESUMO

In brief The effects of resistance exercise and anabolic steroids on lipoprotein profiles were examined in female weight lifters. Steroid users had significantly depressed levels of HDL-C, HDI-2-C (p <.05), and apolipoprotein (apo) A-I compared with nonusers and controls. Nonusers had significantly higher levels of HDL-C and HDL2-C than the controls. Users had significantly less favorable ratios of total cholesterol (TC) to HDL-C, HDL2-C to HDL3-C, and apo A-I to apo B than nonusers or controls. Women who participate in resistance training apparently have significantly better lipoprotein profiles than their sedentary counterparts, but these changes do not offset the deleterious effects of steroid use.

20.
Phys Sportsmed ; 11(10): 99-105, 1983 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27442472

RESUMO

In brief: Sixty-three students aged 7 to 12 years (32 boys, 31 girls) were assessed for coronary heart disease (CHD) risk factors, including family history of CHD, blood pressure, VO2 max, serum lipids, body composition, and history of diabetes mellitus and cigarette smoking. Forty-two percent of the children had one risk factor, and 12% and 3% had two and three risk factors, respectively. This information was used to encourage school administrators and faculty to modify the physical education program, teach health and fitness concepts in the classroom, and develop a rehabilitation program for children at risk.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA