In order to test the hypothesis that dietary restriction may have a negative influence on physiological and psychological adaptation to a judo competition, we examined the effects of weight loss induced by restricting energy and fluid intake on the physiology, psychology, and physical performance of judo athletes. Twenty male judoka were randomly assigned to one of two groups (Group A: called diet, n = 10; height 174.8 +/- 1.9 cm, body weight 75.9 +/- 3.1 kg; they were asked to lose approximately 5 % of their body weight through self-determined means during the week before the competition; Group B: called control, n = 10; height 176.4 +/- 1.1 cm, body weight 73.3 +/- 6.3 kg maintained their body weight during the week before the competition). A battery of tests was performed during a baseline period (T1), on the morning of a simulated competition (T2) and 10 min after the end of the competition (T3). The test battery included assessment for body composition, performance tests, evaluation of mood, determination of metabolic and hormonal responses. Dietary data were collected using a 7-day diet record. The nutrient analysis indicated that all the athletes followed a low carbohydrate diet whatever the period of the investigation. For the Group A, the food restriction (- 4 MJ per day) resulted in significant decreases of the body weight and altered the mood by increasing Fatigue, Tension and decreasing Vigour. Dietary restriction had also a significant influence on metabolic and endocrine parameters and was associated with poor performance. After the competition, significant decreases of the levels in testosterone, T/C ratio, alkali reserve, and free fatty acid were observed in both groups, whereas the plasma concentrations in insulin, ammonia, urea, and uric acid were increased. In conclusion, our results suggest that the combination of energy restriction and intense exercise training, which causes weight reduction before a competition, adversely affects the physiology and psychology of judo athletes and impairs physical performance before the competition. Our data are the first to demonstrate that a competition including five 5-min bouts induced the same changes of physiological and psychological variables and performance whatever the dietary intake (dietary restriction or not) during the seven days before the competition.
Dietary intake, plasma lipids, lipoprotein and apolipoprotein levels, anthropometric measurements and anaerobic performance were studied in eleven judo athletes during a period of weight maintenance (T1) and after a 7d food restriction (T2). Dietary data were collected using a 7-day diet record. Nutrient analysis indicated that these athletes followed a low carbohydrate diet whatever the period of the investigation. Moreover, mean micronutrient intakes were below the French recommendations. Food restriction resulted in significant decreases in body weight. In addition, it had significant influence on triglyceride and free fatty acid, although glycerol, total cholesterol, LDL-C, HDL-C, apolipoprotein A-1 and B did not alter. Left arm strength and 30 s jumping test decreased significantly. The 7 s jumping test was not affected by the food restriction. Regardless of psychological parameters, tension, anger, fatigue and confusion were significantly elevated from T1 to T2; vigor was significantly lower. The data indicated that a 7-day food restriction adversely affects the physiology and psychology of judo athletes and impairs physical performance, possibly due to inadequate carbohydrate and micronutrients.
Muscle cell leakage and hormonal changes were compared immediately after and during the 3 days following a 24 h endurance run (R24h) in 8 subjects, and a 10 h triathlon non-competitive race (T10h) in 6 subjects. The study showed three main differences: 1) plasma enzyme increases were considerably more significant in R24h than in T10h: compared with resting levels, creatine kinase increased x 120 after R24h but only x 2 after T10h; lactic dehydrogenase x 4, as opposed to x 1.5; and transaminases only showed an increase after R24h. The plasma myoglobin increase after R24h was double that found after T10h; 2) for the same magnitude of plasma aldosterone and cortisol after R24h and T10h (3 times the resting levels), a highly significant decrease in urinary Na+ (p less than 0.001) and an increase in urinary K+ (p less than 0.01) were found only after R24h; and 3) the plasma free noradrenaline level increased significantly after R24h (x 2.6) whereas it was unchanged after T10h. In contrast, the plasma level of conjugated dopamine increased only after T10h (x 3.7, p less than 0.05). These results suggest that long-distance running causes more muscular lesions than the triathlon, and that important factors other than aldosterone are probably involved in the regulation of urinary electrolyte excretions during T10h.
Endurance training and/or a fish oil supplemented diet affect cytoplasmic fatty acid binding protein (FABP(c)) content in rat skeletal muscles and heart. After 8 weeks of swimming, trained rats exhibited higher FABP(c) content in the extensor digitorum longus (EDL) and in the gastrocnemius than did control rats (30%). The FABP(c) increase was associated with an increase of citrate synthase activity (85% and 93%, respectively, in the two muscles), whereas lactate dehydrogenase activity decreased significantly. In contrast, in the soleus and in the heart we did not observe any effect of exercise either on FABP(c) or on the metabolic profile. Therefore, increasing oxidative capacities of muscle by exercise resulted in a concomitant increase of the FABP(c) content. Giving a polyunsaturated fatty acid (omega-3) supplemented diet for eight weeks induced a large rise of the FABP(c) in EDL (300%), gastrocnemius (250%), soleus (50%) and heart (15%) without a concurrent accumulation of intramuscular triglycerides or modification of the citrate synthase activity, suggesting that polyunsaturated fatty acids may increase FABP(c) content by up-regulating fatty acid metabolism genes via peroxisome proliferator-activated receptor alpha activation. Endurance trained rats fed with an omega-3 diet had similar FABP(c) content in the gastrocnemius muscle when compared to sedentary omega-3 fed rats, whereas an additive effect of exercise and diet was observed in the EDL. The FABP(c) in the soleus and in the heart of rats fed with omega-3 supplements remained constant whether rats performed exercise or not. As a result, both exercise and omega-3-enriched diet influenced FABP(c) content in muscle. These two physiological treatments presumably acted on FABP(c) content by increasing fatty acid flux within the cell.
The effect of hypercholesterolaemia on the cholesterol and phospholipid content of spermatozoa and seminal plasma was studied. Testosterone and specific markers of the accessory sex glands were also measured. Semen samples from 11 hypercholesterolaemic patients (plasma cholesterol > 6.42 mmol/l, plasma triglycerides < 2 mmol/l) were compared with those of 11 normocholesterolaemic controls (plasma cholesterol < 5.14 mmol/l, plasma triglycerides < 2 mmol/l). Cholesterol, phospholipids and the molar ratio of cholesterol: phospholipids were not significantly different between the two groups of patients either in spermatozoa or in seminal plasma. In hypercholesterolaemic patients the total amount of carnitine in the ejaculate was significantly higher, but there were no significant differences in the levels of acid phosphatase or fructose. There were no significant differences in seminal plasma levels of testosterone in the two groups of subjects. These results suggest that hypercholesterolaemia has no effect on cholesterol and phospholipid levels in spermatozoa and does not cause gross modification of the secretory function of the accessory sex glands.
This study presents an original approach to the effect of regular sporting activity on the metabolism of lipids. We have examined the physiological variations of lipoparticles (Lp) AI, Lp B:CIII, Lp B:E, Lp (a) and the principal lipid markers in 21 high-level rugby players and men of the same age group who take part in no sporting activity (reference group; n = 35). The analysis showed a paradoxical decrease in the high-density lipoprotein fraction of cholesterol (P < 0.05) and in apolipoprotein AI (P < 0.0001), and an increase in the apoprotein B/apoprotein AI ratio in the sportsmen, compared with the reference group. According to these results, physical activity seems to have only a slight influence on anti-atherogenic serum markers. However, the drop in Lp B:E (P < 0.0001) and the static level of Lp AI in the sportsmen indicate a favourable effect of sport on these lipoparticles. The results of this study also highlight the importance of triglycerides and their metabolism. In fact, the lower triglyceride levels (P < 0.05) of the sportsmen justify special attention to diet, especially during a period of competition.
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