TEI Index in elite sprinters and endurance athletes.

AIM: Aerobic training has been reported to have a positive effect on myocardial performance index. The aim of the present study was to examine the myocardial performance index (MPI) in sprinters and endurance athletes. METHODS: A total of 66 elite male athletes (36 sprinter and 30 endurance athletes) and 33 agematched sedentary controls voluntarily participated in the study. The echocardiographic evaluation was performed and TEI index was measured as a marker of myocardial performance index in all groups. RESULTS: Demographic features, training ages and weekly exercise volumes were similar in sprinters and endurance athletes. There were no significant differences in terms of diastolic parameters and among the groups. In sprinters, isovolumetric relaxation time (IVRT) and isovolumetric contraction time (IVCT) were significantly shorter than in controls. In endurance athletes, IVCT was significantly shorter than in controls. Both sprinters and endurance athletes had longer ET compared with controls. TEI Index was significantly lower in sprinters and endurance athletes than in controls. CONCLUSION: Our results suggest that both aerobic and anaerobic training seem to have a positive effect on myocardial performance. This comparable effect might be a result of frequently exercising, especially aerobic exercising in sprinters' training programs.

A cross-sectional analysis of sagittal knee laxity and isokinetic muscle strength in soccer players.

In this cross-sectional study, sagittal knee laxity and isokinetic strength of knee extensor and flexor muscle groups were measured and differences related to leg dominance were evaluated. A total of 44 healthy male soccer players (who had trained regularly at least for the last five years) and 44 sedentary people as their control counterparts were involved in this study. All participants were tested using a KT-1000 knee arthrometer for knee laxity. Isokinetic concentric knee peak torque and hamstring/quadriceps (H/Q) ratio were also measured at 60, 180, 300 degrees/s through a Cybex 2 - 340 dynamometer. Posterior laxity in the non-dominant side of soccer players was significantly higher than in the dominant side (p < 0.005) while there were no significant anterior and total anteroposterior (total AP) laxity differences in both groups. Soccer players had significantly lower anterior and total AP laxity values than controls (p < 0.0001) while there was no significant difference between posterior laxity values in both sides. Dominant extremity demonstrated significantly higher knee flexor peak torque and H/Q ratio at 180 degrees /s in soccer players (p < 0.05). Similarly in sedentary controls, H/Q ratio at 60 degrees /s of the dominant side was significantly higher than that in the non-dominant side (p < 0.05). Soccer players had significantly higher extensor and flexor peak torque values and H/Q ratios than sedentary subjects for both extremities. In both groups, there were no significant correlations between knee laxity and isokinetic knee extensor and flexor strength and H/Q ratios except weak negative correlation between posterior knee laxity and isokinetic extensor peak torque at 60, 180 and 300 degrees /s (p < 0.005, r = - 0.43, p < 0.05, r = - 0.39, p < 0.05, r = - 0.32 respectively) in the non-dominant side of soccer players and at 300 degrees /s (p < 0.05, r = - 0.32) in the non-dominant side of controls. Soccer players demonstrated significantly less sagittal knee laxity and higher isokinetic strength of the knee flexors and extensors compared to sedentary controls. Isokinetic strength difference was found to be higher for the flexor muscle group. Further prospective studies are needed to explain whether the increased H/Q ratio decreases the risk of ligamentous injury.

Effects of continuous and interval running training on serum growth and cortisol hormones in junior male basketball players.

Effects of two different eight-week aerobic training programs consisting of continuous (CR) or extensive interval running (IR) on serum growth (GH) and cortisol hormones in 33 male basketball players aged 15-16 were assessed. The CR group ran 4.8 km and the IR group ran 4 x 1.2 km, using equal work-to-rest ratio, three times per week. Aerobic power scores of all subjects and anaerobic power marks of the training subjects increased (p<0.01). Upon exertion, though serum GH levels increased in both exercise groups (p<0.01) prior to and following training; cortisol levels increased only in the IR group prior to training, and in both exercise groups following training (p<0.05). Following the eight week period, resting cortisol levels rose in the training (p<0.05) and control (p<0.01) groups. To conclude, an 8-week training program consisting of continuous or extensive interval running has been effective on acute GH and cortisol secretion in 15-16 year-old male athletes.

Glucose metabolism and catecholamine responses during physical exercise in non-insulin-dependent diabetes.

Blood glucose, lactate, insulin, C-peptide, norepinephrine and epinephrine concentrations were determined in non-insulin-dependent diabetic patients and in healthy controls before, during and after moderate exercise, to evaluate the effects of physical exercise on glucoregulation. Ten diabetic and ten healthy control females bicycled 14 minutes at 60% of their maximal heart rates. In the diabetic patients, there were no significant changes in blood glucose levels post-exercise, while in controls the 60 minute post-exercise levels were higher than those measured in mid-exercise (p < 0.05). Lactate concentrations increased with exercise in both groups in a similar manner, with highest values at the end of exercise. No significant changes in insulin and C-peptide levels were induced with exercise in either group. Norepinephrine and epinephrine concentrations increased 2.5-3 fold with exercise in both groups (p < 0.05 for all values) but in the diabetics an earlier and prolonged catecholamine response was observed. We propose that catecholamines prevent hypoglycaemia during exercise when changes in insulin and C-peptide do not occur. In diabetic patients with good metabolic control, the glucoregulatory response to exercise is not worse than in anthropometrically similar controls with similar levels of fitness.

Evaluation of iron metabolism indices and their relation with physical work capacity in athletes.

OBJECTIVE: To evaluate the relation between iron status and physical working capacity, and to assess the effect of oral iron treatment on these variables, in athletes with borderline iron status. METHODS: Blood haemoglobin (Hb), packed cell volume (PCV), red blood cell count (RBC), serum iron, total iron binding capacity (TIBC), and ferritin determinations were compared in 71 male and 18 female athletes participating in various sports and in matched male (n = 11) and female (n = 8) controls. The first aim was to assess the relations between these variables and performance in a physical work capacity test (PWC170). Oral iron treatment (175-350 mg ferrous fumarate daily) was provided for three weeks to six male and five female athletes with borderline Hb concentrations, to determine the effects of such treatment on both iron status and performance. RESULTS: Among females, handball players had the lowest serum ferritin concentrations (P < 0.05), the highest TIBC values, and lowest PWC170 scores (P < 0.01); runners had the highest ferritin concentrations and PWC170 scores (P < 0.01). There were significant correlations (P < 0.01) between PWC170 and PCV, serum ferritin, and transferrin saturation of female athletes. Hb, serum iron, serum ferritin, and transferrin saturation increased with iron treatment in both males (P < 0.01) and females (P < 0.05). CONCLUSIONS: Serum ferritin determination may prove a valuable addition to the screening of athletes and may indicate the need for iron treatment, even though a causal effect on improvement of work capacity may not be present.