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PubMed1992

Glucose transporter number, function, and subcellular distribution in rat skeletal muscle after exercise training.

Endurance exercise training can result in increased rates of insulin-stimulated glucose uptake in skeletal muscle; however, this effect may be lost rapidly once training ceases. To examine a mechanism for these changes, the skeletal-muscle glucose transport system of female rats exercise-trained in wheelcages for 6 wk were studied against a group of untrained female rats. The trained rats were studied immediately following and 2 and 5 days after removal from wheelcages; both trained and untrained rats were studied 30 min after insulin (90 nmol/rat, intraperitoneal) or saline injection. The total number of skeletal-muscle plasma-membrane glucose transporters (R0), total muscle-homogenate and plasma-membrane GLUT4 protein, and rates of plasma-membrane vesicle D-facilitated glucose transport were higher in the exercise-trained rats immediately after exercise training and did not decrease significantly during the 5 days after cessation of training. On the other hand, exercise training did not alter microsomal-membrane total glucose-transporter number or GLUT4 protein, nor did training alter GLUT1 protein in total muscle homogenates nor either membrane fraction. The carrier-turnover number, an estimate of average functional activity of glucose transporters in the plasma membrane, was elevated slightly, but not significantly, in the trained muscle. In both the trained and untrained muscle, insulin administration resulted in translocation of glucose transporters from the microsomal-membrane fraction to the plasma membrane and an increase in the carrier-turnover number.(ABSTRACT TRUNCATED AT 250 WORDS)

4-Nitrophenylphosphatase↗

PubMed2002

Familial aggregation of blood lipid response to exercise training in the health, risk factors, exercise training, and genetics (HERITAGE) Family Study.

BACKGROUND: Fasting levels of plasma lipids and lipoproteins are reported to improve with regular exercise training. However, little is known on whether the training responses are influenced by heritable factors. METHODS AND RESULTS: The lipid profile was assessed in 115 black (224 individuals) and 99 white families (469 individuals), who participated in the HERITAGE Family Study, while in a sedentary state (baseline visit) and after exercise training for 20 weeks (post visit). Variables included total cholesterol, triglyceride, low-density lipoprotein cholesterol (LDL-C), apolipoprotein B (ApoB), high-density lipoprotein cholesterol (HDL-C), apolipoprotein A-I, and HDL-C subfractions 2 (HDL2-C) and 3 (HDL3-C). Familial correlations for the training responses (Delta=post-baseline) were significant for most variables, and the percent variance accounted for by familial factors (ie, maximal heritabilities) ranged from 25% to 38%. Exceptions were for higher heritabilities near 60% for DeltaApoB in blacks and DeltaHDL2-C in whites and a lower estimate of zero for DeltaLDL-C in blacks. CONCLUSIONS: Heritable factors in part determine lipid profile responses to regular exercise. Maximal heritabilities were similar across ethnic groups and variables, except for DeltaLDL-C, DeltaApoB, and DeltaHDL2-C. Molecular studies to identify the markers and genes associated with these influences are currently underway.

Adolescent↗

PubMedDate not supplied

Neurohormonal abnormalities in heart failure: impact of exercise training.

Endurance exercise training appears to beneficially alter the clinical course of chronic heart failure. The specific mechanisms responsible for exercise-induced benefits, however, are not completely understood. This review examines the impact of endurance exercise training on neurohormonal mechanisms, which play a central role in the progression of chronic heart failure. Few studies, however, have been specifically designed to elucidate exercise-induced mechanisms responsible for the suppression of neurohormonal activation in patients with chronic heart failure and the literature on this topic is derived from a limited number of small, single-center studies. The available data suggests that endurance exercise training programs of moderate duration (approximately 16 weeks) are efficacious in suppressing circulating levels of catecholamines, angiotensin II, arginine vasopressin, and aldosterone. Additionally, endurance exercise training improves baroreceptor sensitivity and heart rate variability, suggesting that exercise ameliorates the autonomic derangement in chronic heart failure by increasing the parasympathetically mediated component of heart rate variability. Pharmacologic suppression of sympathetic activity has proved, by and large, to be successful at reducing mortality in patients with chronic heart failure. Exercise-induced modulation of sympathetic activity may also be instrumental at reducing morbidity and mortality but this has not been carefully investigated and is a fertile area for further research.

Disease Progression↗

PubMed2024

Acute strength exercise training impacts differently the HERV-W expression and inflammatory biomarkers in resistance exercise training individuals.

BACKGROUND: Human Endogenous Retroviruses (HERVs) are fossil viruses that composes 8% of the human genome and plays several important roles in human physiology, including muscle repair/myogenesis. It is believed that inflammation may also regulate HERV expression, and therefore may contribute in the muscle repair, especially after training exercise. Hence, this study aimed to assess the level of HERVs expression and inflammation profile in practitioners' resistance exercises after an acute strength training session. METHODS: Healthy volunteers were separated in regular practitioners of resistance exercise training group (REG, n = 27) and non-trained individuals (Control Group, n = 20). All individuals performed a strength exercise section. Blood samples were collected before the exercise (T0) and 45 minutes after the training session (T1). HERV-K (HML1-10) and W were relatively quantified, cytokine concentration and circulating microparticles were assessed. RESULTS: REG presented higher level of HERV-W expression (~2.5 fold change) than CG at T1 (p<0.01). No difference was observed in the levels of HERV-K expression between the groups as well as the time points. Higher serum TNF-α and IL-10 levels were verified post-training session in REG and CG (p<0.01), and in REG was found a positive correlation between the levels of TNF-α at T1 and IL-10 at T0 (p = 0.01). Finally, a lower endothelial microparticle percentage was observed in REG at T1 than in T0 (p = 0.04). CONCLUSION: REG individuals exhibited a significant upregulation of HERV-W and modulation of inflammatory markers when compared to CG. This combined effect could potentially support the process of skeletal muscle repair in the exercised individuals.

Humans↗

PubMed2002

Effects of exercise training plus normalization of hematocrit on exercise capacity and health-related quality of life.

The limitation to exercise capacity in hemodialysis patients has been attributed to anemia. We report the effects of normalization of hematocrit levels by using r-hu-recombinant erythropoietin and exercise training on exercise capacity and self-reported physical functioning in hemodialysis patients. Sixty-five patients were randomized into 1 of 4 groups: usual hematocrit (30%-33%) with no exercise training (UH); usual hematocrit (30%-33%) plus exercise training (UHX); normalized hematocrit (40%-42%) with no exercise training (NH); and normalized hematocrit (40%-42%) plus exercise training (NHX). Treadmill exercise testing was conducted at baseline and at 5 months after the initiation of the interventions. Analysis was performed on the data collapsed for 48 patients who met the criteria for hematocrit and exercise adherence and completed both baseline and post intervention (5.6 +/- 1.6 months) testing. Significant effects of exercise were found in peak oxygen uptake measurements (P = 0.03) and in self-reported physical functioning as measured by the Short Form-36 questionnaire (P = 0.01). There was a significant effect of hematocrit on the General Health scale on the SF-36 (P = 0.03). The changes in peak oxygen uptake with exercise training were small and levels remained lower than age-predicted values at the end of the study. These results indicate that there are other physiologic limitations to exercise capacity that are not overcome by exercise training or normalization of hematocrit. The effects of exercise training on self-reported physical functioning may be of clinical importance because these scores have been shown to be highly predictive of outcomes such as hospitalizations and mortality in hemodialysis patients.

Adult↗

PubMed1993

Vitamin E status does not affect the responses to exercise training and acute exercise in female rats.

Responses of vitamin E-depleted female rats to acute exercise and chronic exercise training were tested. Rats were fed either a control diet (+E rats) or a vitamin E-depleted diet (-E rats). After 8 wk, subgroups of the +E and -E rats performed treadmill exercise for 45 min at 28 m/min, 15% grade, and were immediately killed. Vitamin E concentrations were 80-90% lower in liver, heart and muscles in -E rats as determined by HPLC. There was no difference between +E and -E rats in blood lactate concentration, creatine kinase, lipid peroxidation indices, hematocrit or hemoglobin concentration following acute exercise. Remaining rats were either trained for a further 8 wk at 40 m/min, 15% incline for up to 60 min/d or served as untrained controls. No differences in training tolerance were seen between diet groups, with 64% of +E rats and 71% of -E rats consistently completing 60 min of daily training. The training induced similar adaptive elevations in succinate dehydrogenase activity (31-107%) in various hind limb muscles of both +E and -E rats. Trained +E rats had lower vitamin E concentrations in some but not all tissues when compared with untrained +E controls. These results suggest that consumption of a vitamin E-free diet for 8 wk did not result in differences in blood indices associated with exercise stress or in the ability to perform a submaximal acute exercise test when compared with controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1986

Thermogenesis with relation to exercise and exercise-training.

Exercise-training at environmental temperatures outside the thermal neutral zone, causes thermoregulatory adaptive reactions. In the heat, sweat efficiency is enhanced thus reducing the incidence of hyperthermia while in the cold discomfort and danger of frostbite are minimized by an improved cutaneous circulation specially in the extremities. Over long periods of time exercise does not affect thermogenesis except when refeeding. It is suggested that the reduced postprandial heat production reported in exercise-trained subjects is related to changes in nutrient metabolism which in turn could be related to insulin and norepinephrine modified actions.

Body Temperature Regulation↗

PubMed1984

Maximum coronary blood flow and minimum coronary resistance in exercise-trained dogs.

Exercise training has been found to increase coronary vascularity of the heart in experimental animals. Maximum coronary flow and minimum coronary resistance were determined in 16 dogs with the injection of microspheres (15 micron) into the left atrium at rest and during the intravenous infusion of adenosine (0.7 mg X min-1 X kg-1). Heart rate was paced at 150 beats/min. Dogs were divided into three groups with microsphere injections made before and after 4-5 wk of daily exercise (group 1); before and after 8-10 wk of daily exercise (group II); and before and after 8-10 wk of cage rest (group III). Results of average left ventricular maximum myocardial flow before and after daily exercise were 4.08 +/- 0.34 and 4.89 +/- 0.33 ml X min-1 X g-1 for group I, 5.13 +/- 0.32 and 5.55 +/- 0.56 ml X min-1 X g-1 for group II, and 5.24 +/- 0.43 and 4.34 +/- 0.55 ml X min-1 X g-1 for group III. Arterial pressure, maximum coronary flow, and minimum coronary resistance were not significantly different before and after any condition in all three groups of dogs. Peak reactive hyperemia coronary flow was not altered by daily exercise. These results indicate that maximum coronary flow and minimum coronary resistance were not altered by either 4-5 or 8-10 wk of exercise training.

Adenosine↗

PubMed2002

Substrate oxidation, obesity and exercise training.

Regular physical exercise is of the utmost importance in the treatment of obesity because exercise is one of the factors determining long-term weight maintenance in weight reduction programmes and because exercise has been associated with a reduced risk for developing type 2 diabetes mellitus and cardiovascular disease. Obesity is associated with an impaired utilization of fat as a fuel during post-absorptive conditions, during beta-adrenergic stimulation and possibly during exercise, although the latter data are controversial. One of the underlying mechanisms for the positive effect of exercise training in obesity may be related to its effects on fat utilization because exercise training has been shown to increase basal fat oxidation and exercise fat oxidation in lean volunteers. Data on the effect of aerobic exercise training on exercise fat oxidation are controversial, whereas the available data indicate that exercise training may not be able to increase resting fat oxidation or 24-hour fat oxidation in obese subjects. Because disturbed muscle fat oxidation may be a primary event in the aetiology of obesity it is of the utmost importance to obtain more information on how and whether exercise training may be able to compensate for these impairments.

Adipose Tissue↗

PubMed2001

Effects of endurance exercise training on plasma HDL cholesterol levels depend on levels of triglycerides: evidence from men of the Health, Risk Factors, Exercise Training and Genetics (HERITAGE) Family Study.

High density lipoprotein (HDL) cholesterol concentrations have been shown to increase with regular endurance exercise and, therefore, can contribute to a lower risk of coronary heart disease in physically active individuals compared with sedentary subjects. Although low HDL cholesterol levels are frequently observed in combination with hypertriglyceridemia, some individuals may be characterized by isolated hypoalphalipoproteinemia, ie, low HDL cholesterol levels in the absence of elevated triglyceride (TG) concentrations. The present study compared the responses of numerous lipoprotein-lipid variables to a 20-week endurance exercise training program in men categorized on the basis of baseline TG and HDL cholesterol concentrations: (1) low TG and high HDL cholesterol (normolipidemia), (2) low TG and low HDL cholesterol (isolated low HDL cholesterol), (3) high TG and high HDL cholesterol (isolated high TGs), and (4) high TGs and low HDL cholesterol (high TG/low HDL cholesterol). A series of physical and metabolic variables was measured before and after the training program in a sample of 200 men enrolled in the Health, Risk Factors, Exercise Training and Genetics (HERITAGE) Family Study. At baseline, men with high TG/low HDL cholesterol had more visceral adipose tissue than did men with isolated low HDL cholesterol and men with normolipidemia. The 0.4% (not significant) exercise-induced increase in HDL cholesterol levels in men with isolated low HDL cholesterol suggests that they did not benefit from the "HDL-raising" effect of exercise. In contrast, men with high TG/low HDL cholesterol showed a significant increase in HDL cholesterol levels (4.9%, P<0.005). Whereas both subgroups of men with elevated TG levels showed reductions in plasma TGs ( approximately -15.0%, P<0.005), only those with high TG/low HDL cholesterol showed significantly reduced apolipoprotein B levels at the end of the study (-6.0%, P<0.005). Multiple regression analyses revealed that the exercise-induced change in abdominal subcutaneous adipose tissue (10.6%, P<0.01) was the only significant correlate of the increase in plasma HDL cholesterol with training in men with high TG/low HDL cholesterol. Results of the present study suggest that regular endurance exercise training may be particularly helpful in men with low HDL cholesterol, elevated TGs, and abdominal obesity.

Adult↗

PubMed1979

Effect of endurance exercise training on plasma pancreatic polypeptide concentration during exercise.

The effect of exercise on human pancreatic polypeptide (hPP) levels was evaluated in five subjects preceding and following a conditioning program. During 90 min of exercise, the plasma concentration of hPP rose to a peak value five times higher than the resting level. After 2 mo of endurance exercise training, exercising at the same absolute work load resulted in only a twofold increase in hPP levels. Even at a higher work load, plasma hPP levels were significantly lower than the values observed prior to conditioning. These results show that plasma hPP concentrations rise during exercise and the magnitude of this response is significantly lower after 2 mo of endurance exercise training.

Adult↗

PubMed2001

Calcium buffering in coronary smooth muscle after chronic occlusion and exercise training.

OBJECTIVE: Exercise promotes "sarcoplasmic reticulum (SR) Ca2+ unloading" in porcine coronary smooth muscle, resulting in decreased agonist-induced Ca2+ release. We studied Ca2+ handling in healthy, non-occluded right coronary artery cells from hearts chronically occluded at the circumflex artery. METHODS: Myoplasmic free Ca2+ (Ca(m)) was assessed with fura-2 in cells from sedentary (n=8) and aerobically exercise-trained (n=6) female Yucatan pigs after 6-month circumflex artery ameroid occlusion (OCC) and in cells from non-occluded, sedentary pigs (SED, n=5). First, Ca influx was induced by 80 mM KCl depolarization (priming step) followed by 5 mM caffeine to elicit maximal Ca2+ release and depletion. The SR was Ca-loaded again by depolarization and then exposed to caffeine after 2- or 11-min recovery to compare SR Ca2+ unloading. RESULTS: Baseline Ca(m), caffeine-induced peak Ca(m), and depolarization-induced maximum Ca(m) were decreased, and depolarization-induced time-to-half-maximum was increased in OCC vs. SED pigs, suggesting a tonic Ca2+ buffering (lowering) effect of occlusion. Exercise did not alter these effects. SR Ca2+ unloading occurred only in SED, as evidenced by decreased caffeine-induced Ca2+ release after 11 min of recovery, and was inhibited by low extracellular Na+. CONCLUSIONS: SR Ca2+ unloading can be demonstrated in coronary smooth muscle from sedentary pigs using a novel SR Ca2+ unloading protocol, and Ca2+ unloading partly depends on Na+-Ca2+ exchange activity. Furthermore, SR Ca2+ unloading in cells from non-occluded right coronary arteries of chronically circumflex-occluded pig hearts was not altered by exercise, perhaps due to enhanced tonic Ca2+ extrusion versus cells from normal, sedentary animals.

Adaptation, Physiological↗

PubMed1992

Cardiac response to acute coronary artery occlusion in exercise-trained dogs.

Exercise training is thought to exert a beneficial effect on cardiovascular function, but its effect in the normal heart following acute coronary artery occlusion is still uncertain. Studies were performed in 12 untrained (UT) and 14 endurance-trained (ET) pentobarbital anesthetized dogs. Left ventricular pressure (LVP), heart rate (HR), percent regional myocardial segmental shortening (%SL), and peripheral coronary pressure (PCP) distal to the occlusion were measured during control conditions and during a 2-min circumflex artery occlusion (CAO). During CAO, LVP, dP/dtmax, and %SL in the ischemic region were significantly reduced in both UT and ET dogs. There was no significant difference between the two groups. In addition, PCP decreased to 27 +/- 5 mm Hg and 26 +/- 9 mm Hg in the UT and ET groups, respectively, during CAO indicating no difference in coronary collateral perfusion between the groups. Regional myocardial blood flow was measured using tracer microspheres in eight of the UT and six of the ET dogs, and the decrease in blood flow to the ischemic zone during CAO was similar in both groups. These results indicate that 12-wk of endurance training does not exert a protective effect on myocardial contractile function or on myocardial perfusion in the central ischemic region during CAO in the anesthetized dog.

Acute Disease↗

PubMed1998

Self-management of fibromyalgia: the role of formal coping skills training and physical exercise training programs.

There has been growing interest in the use of formal self-management training programs for people with fibromyalgia (FM). In these programs, health care professionals serve as trainers and provide education about FM and guided instruction in specific self-management strategies. A review of the literature on formal self-management training programs for FM suggests that they can be divided into groups: 1) those emphasizing training in coping skills (e.g., relaxation, activity pacing, and problem-solving techniques), and 2) those emphasizing training in physical exercise (e.g., cardiovascular fitness, strength, and endurance training). In this article, we review studies that have tested the efficacy of both types of programs. In addition, we identify key individual and contextual variables that are related to outcome and highlight future directions in the research and development of self-management programs.

Adaptation, Psychological↗

PubMed1996

[The effect of blood AST, ALT and lactate after short and middle distance exercise training].

Twenty-four nursing college students aged 16 and 17 years were selected as research subjects and divided into two groups. Group A comprised 12 individuals who were trained for short distance running (5km/day) over a four-week period, while group B was trained for middle distance running (7km/day) during the same period. Blood AST (aspartate aminotransferase), ALT (alanine aminotransferase) and lactate were performed at rest (before training) and after exercise every week. After both short and middle distance exercise training, the lactate values after 1-3 week(s) training period were persistently higher than those before training and the differences between then are significant. However, the lactate value after 4 weeks training period is lower than that after the third week training. There are significant differences between the AST values after 1-4 week(s) training period and those before exercise in short distance exercise training. There are no significant differences between the AST values after training and those before exercise in middle distance exercise training. The ALT values after 1-4 week(s) training period were lower than those before exercise in short and middle distance exercise training. In conclusion, after 4 weeks training, the lactate and AST values can't reduce to those before training in middle distance exercise training, and the lactate value in short distance exercise training is the same as former. Further investigation is needed.

Adolescent↗

PubMed2003

Isolated heart responsiveness to beta-simulation after exercise training in obesity.

PURPOSE: Exercise training results in many health benefits, but few studies have focused on whether exercise training might attenuate the adverse effects of obesity on heart function. Therefore, the purpose of this study was to determine whether exercise training attenuated obesity-related decreases in systolic contractile function in response to beta-adrenergic stimulation, using the rabbit model of obesity. METHODS: Female New Zealand white rabbits were divided into four groups: lean sedentary, lean exercise-trained, obese sedentary, and obese exercise-trained. Obese rabbits were fed an ad libitum high-fat diet. Exercise-trained rabbits underwent a 12-wk progressive treadmill exercise training protocol. After 12 wk, the Langendorff isolated heart method was used to study developed pressure, +dP/dt, and -dP/dt responses to increasing concentrations of isoproterenol (10(-9)--3 x 10(-7) M). Log concentration-response data were fit to a sigmoidal function, using a four-parameter (minimum, maximum, EC(50), slope) logistic equation. Groups were compared using a 2 x 2 analysis of variance. RESULTS: Although obesity shifted the concentration-response curves for developed pressure, +dP/dt, and -dP/dt to the right as indicated by an increase in the EC(50) (P < or = 0.05), there was no effect of exercise training on any of the logistic regression parameters. EC(50) (log M) values for combined lean versus combined obese were -8.50 +/- 0.7 vs -8.20 +/- 0.09 (developed pressure), -8.04 +/- 0.06 vs -7.68 +/- 0.07 (+dP/dt), and -8.17 +/- 0.07 vs -7.91 +/- 0.09 (-dP/dt). CONCLUSION: These results confirm the negative effect of obesity on responsiveness of the isolated heart to beta-adrenergic stimulation but indicate that exercise training does not significantly attenuate obesity-related changes.

Adrenergic beta-Agonists↗

PubMed1999

Influence of high-intensity exercise training on the ventilatory response to exercise in patients with reduced ventricular function.

BACKGROUND: Exercise training increases exercise capacity in patients with reduced ventricular function in part through improved skeletal muscle metabolism, but the effect training might have on abnormal ventilatory and gas exchange responses to exercise has not been clearly defined. METHODS: Twenty-five male patients with reduced ventricular function after a myocardial infarction were randomized to either a 2-month high-intensity residential exercise training program or to a control group. Before and after the study period, upright exercise testing was performed with measurements of ventilatory gas exchange, lactate, arterial blood gases, cardiac output, and pulmonary artery and wedge pressures. RESULTS: In the exercise group, peak VO2 and VO2 at the lactate threshold increased 29 and 39%, respectively, whereas no increases were observed among controls. Maximal cardiac output increased only in the exercise group (1.7 L x min(-1), P < 0.05), and no changes in rest or peak exercise pulmonary pressures were observed in either group. At baseline, modest inverse relationships were observed between pulmonary wedge pressure and peak VO2 both at rest (r = -0.56, P < 0.05) and peak exercise (r = -0.43, P < 0.05). Maximal VE/VCO2 was inversely related to maximal cardiac output (r = -0.72, P < 0.001). Training did not have a significant effect on these relationships. Training lowered VE/VO2, heart rate, and blood lactate levels at matched work rates throughout exercise and tended to lower maximal Vd/Vt. The slope of the relationship between VE and VCO2 was reduced after training in the exercise group (0.33 pre vs 0.27 post, P < 0.01), whereas control patients did not differ. CONCLUSIONS: Exercise training among patients with reduced left ventricular function results in a systematic improvement in the ventilatory response to exercise. Training increased maximal cardiac output, tended to lower Vd/Vt, and markedly improved the efficiency of ventilation. Peak VO2 and ventilatory responses to exercise were only modestly related to pulmonary vascular pressures, and training had no effect on the relationships between exercise capacity, ventilatory responses, and pulmonary pressures.

Anaerobic Threshold↗

PubMed2001

Longitudinal changes in reproductive hormones and menstrual cyclicity in cynomolgus monkeys during strenuous exercise training: abrupt transition to exercise-induced amenorrhea.

Cross-sectional studies of exercise-induced reproductive dysfunction have documented a high proportion of menstrual cycle disturbances in women involved in strenuous exercise training. However, longitudinal studies have been needed to examine individual susceptibility to exercise-induced reproductive dysfunction and to elucidate the progression of changes in reproductive function that occur with strenuous exercise training. Using the female cynomolgus monkey (Macaca fascicularis), we documented changes in menstrual cyclicity and patterns of LH, FSH, estradiol, and progesterone secretion as the animals developed exercise-induced amenorrhea. As monkeys gradually increased running to 12.3 +/- 0.9 km/day, body weight did not change significantly although food intake remained constant. The time spent training until amenorrhea developed varied widely among animals (7-24 months; mean = 14.3 +/- 2.2 months) and was not correlated with initial body weight, training distance, or food intake. Consistent changes in function of the reproductive axis occurred abruptly, one to two menstrual cycles before the development of amenorrhea. These included significant declines in plasma reproductive hormone concentrations, an increase in follicular phase length, and a decrease in luteal phase progesterone secretion. These data document a high level of interindividual variability in the development of exercise-induced reproductive dysfunction, delineate the progression of changes in reproductive hormone secretion that occur with exercise training, and illustrate an abrupt transition from normal cyclicity to an amenorrheic state in exercising individuals, that is not necessarily associated with weight loss.

Amenorrhea↗