Medicina Sportiva 2004 vol. 8 nr. 1

ANTI-AGING INTERVENTIONS:
THE EFFECTS OF DIETARY RESTRICTION AND EXERCISE
Barbara Kłapcińska

Department of Physiological and Medical Sciences, Biochemistry Unit, Academy of Physical Education, Katowice, Poland

Abstract
Restriction of food intake and regular physical activity retard age-associated decline in functional and cognitive capacities and prevent age-related diseases in rodents, non-human primates and humans. This review focuses on the possible biological mechanisms underlying the anti-aging action of these interventions. The following mechanisms are considered: (1) attenuation of oxidative stress; (2) up-regulation of antioxidant defenses; (3) modulation of glycemia and insulinemia; (4) enhancement and protection of brain function.
Key words: aging, dietary restriction, exercise
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Peak Cortisol Response to Exhausting Exercise:
Effect of Blood Sampling Schedule
W. Daly, C. Seegers, S. Timmerman, A.C. Hackney

Endocrine Section - Applied Physiology Laboratory, University of North Carolina, Chapel Hill, North Carolina,
USA

Abstract
Introduction: Strenuous exercise provokes increases in circulating cortisol levels. When the peak cortisol response to exercise occurs is a point of contention, as some research suggests the peak response coincides with the end of exercise while other indicate it is delayed and occurs during recovery.
Aim of the study: This study examined when peak cortisol levels occur in response to intensive, exhausting exercise of a prolonged nature.
Methods: Thirty-four healthy male subjects ran on a treadmill until volitional exhaustion. Blood specimens were analyzed for cortisol levels immediately at the end of exercise and at 30, 60, and 90 minutes into recovery.
Results: A significantly greater number (25/34; i.e., 73.5%) of the peak cortisol responses occurred during the recovery period (at 30 – 90 minutes) after the subjects reached volitional exhaustion and had stopped exercising.
Conclusion: The findings suggest that if researchers are interested in assessing the peak cortisol response to exhausting exercise they should continue blood sampling for approximately 1 hour into the recovery period.
Key words: endocrines, hormones, recovery, stress
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LIPID AND LIPOPROTEIN PROFILE IN REGULARLY MENSTRUATING PHYSICALLY ACTIVE FEMALE OC-NON-USERS AND USERS AS COMPARED TO MEN OF MATCHED AGE AND PHYSICAL ACTIVITY

Grażyna Lutosławska, Marzena Niedbalska, Ewa Byszewska-Szpocińska, Elżbieta Skierska, Anna Kęska

1 Department of Biochemistry, Academy of Physical Education, Warsaw, Poland
2 Department of Radioimmunology, Radioisotope Centre POLATOM, Swierk, Poland,
3 Department of Biology, Academy of Physical Education, Warsaw, Poland

Abstract
Introduction: Vigorous physical activity depresses ovary function, circulating sex hormones and alters plasma lipid and lipoprotein profile which in amenorrheic females is less favorable than in their regularly menstruating counterparts. However, data concerning plasma lipid and lipoprotein profile in physically active, regularly menstruating females using and non-using oral contraceptive (OC) in comparison with males of similar physical activity are limited.
Aim of the study: This study was aimed at evaluation of plasma lipid and lipoprotein, glucose and insulin levels in regularly menstruating female physical education students (OC-users and non-users) in comparison with males.
Methods: A total of 113 subjects volunteered to participate in the study. Biochemical variables (total cholesterol (TC), HDL- and LDL-cholesterol (HDL-C and LDL-C), triacylglycerols (TG), free fatty acid (FFA), glycerol, glucose) were determined in fasting blood plasma using colorimetric methods and commercial kits (Randox Laboratories, United Kingdom). Insulin was measured by a standard radioimmunoassay and monoclonal antibody against insulin (IRMA-POLATOM. Poland).
Results: There were no between-group differences in insulin, FFA and glycerol plasma levels and Quantitative Insulin Check Index (QUICKI). However, plasma lipoprotein profiles in female OC-non-users were less favorable than in males due to higher TC and LDL-C concentrations. This difference was even more evident when the TC/HDL-C ratio was taken into consideration. In contrast, in female OC-users plasma HDL-C was significantly higher than in OC-non-users and in males. Despite slightly higher TC in OC-users. The TC/HDL-C ratio was lower than in both other groups. In males there was a significant correlation between plasma glycerol and TG levels (r=0.376, p<0.01). In contrast, in female OC-non-users such a correlation was found between plasma glycerol and LDL-C concentrations (r=0.437, p<0.001). In female OC-users plasma glycerol mostly affected plasma HDL-C levels without an effect on plasma TG and LDL-C levels.
Conclusions: Since our subjects did not differ with respect to dietary habits it is postulated that vigorous physical activity in premenopausal females promotes undesirable changes in plasma lipoprotein profile and slightly, but significantly affects adipose tissue contribution to lipoprotein synthesis.
Key words: physical activity, lipids, lipoproteins, males, female OC-non-users, female OC-users
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Effects of strenuous training and repeated cycles of weight loss on leptin and sex hormones in elite female wrestlers

Maria Psatha^1,2, Des Gilmore², Fani Psatha³ & Athanasios Dessypris⁴

1Division of Sports Medicine, Department of Medicine & Therapeutics,
2Institute of Biomedical and Life Sciences, University of Glasgow, UK,
3Department of Physical Education & Sport Science,
4Department of Biology, University of Athens, Greece


Abstract

Introduction: Subtle menstrual disturbances due to metabolic and hormonal alterations have been shown to affect a large proportion of elite female athletes. These alterations include leptin and sex hormones that have been shown to be related to body fat.
Aim of the study: We wished to determine if strenuous activity and repeated cycles of weight loss and regain affect leptin and other hormone levels in competitive female wrestlers.
Methods: Menstrual history, anthropometry, ovarian ultrasound scan, and hormone tests [leptin, oestradiol (E2), progesterone (P), luteinising hormone (LH), follicle-stimulating hormone (FSH)] were performed in a group of elite female wrestlers (A) and a group of aged-matched sedentary controls (C).
Results: Three athletes and no controls were oligomenorrheic (3-10 menses/yr). However the ovarian ultrasound scans were normal for all subjects. There was no significant difference between groups in age, height, or age at menarche. The correlation between body fat (%) and leptin was linear with regression coefficients (r= 0.89 (A) and r=0.83 (C)) being similar in both groups. However, a significant difference was observed between the two groups for leptin levers (P<0.05). E2 and P levels were within the normal physiological range in both groups (E2 > 25 pg*ml-1; P > 2.5 ng*ml-1) with P levels being lower for the athletes but the difference was no significant. Serum LH and FSH levels were also within the normal range (>1.5 IU*L-1).
Conclusions: No menstrual abnormalities were observed during the period of the study. Leptin levels were significantly lower for the wrestlers.
Key words: female, wrestling, weight loss, leptin, hormones
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