No abstract

Cardiac power output (CPO) is an integrative measure of overall cardiac function as it accounts for both, flow- and pressure-generating capacities of the heart. The purpose of the present study was twofold: (i) to assess cardiac power output and its response to exercise in athletes and non-athletes and (ii) to determine the relationship between cardiac power output and reserve and selected measures of cardiac function and structure. Twenty male athletes and 32 age- and gender-matched healthy sedentary controls participated in this study. CPO was calculated as the product of cardiac output and mean arterial pressure, expressed in watts. Measures of hemodynamic status, cardiac structure and pumping capability were assessed by echocardiography. CPO was assessed at rest and after peak bicycle exercise. At rest, the two groups had similar values of cardiac power output (1·08 ± 0·2 W versus 1·1 ± 0·24 W, P>0·05), but the athletes demonstrated lower systolic blood pressure (109·5 ± 6·2 mmHg versus 117·2 ± 8·2 mmHg, P<0·05) and thicker posterior wall of the left ventricle (9·8 ± 1 mm versus 9 ± 1·1 mm, P<0·05). Peak CPO was higher in athletes (5·87 ± 0·75 W versus 5·4 ± 0·69 W, P<0·05) as was cardiac reserve (4·92 ± 0·66 W versus 4·26 ± 0·61 W, P<0·05), respectively. Peak exercise CPO and reserve were only moderately correlated with end-diastolic volume (r = 0·54; r = 0·46, P<0·05) and end-diastolic left ventricular internal diameter (r = 0·48; r = 0·42, P<0·05), respectively. Athletes demonstrated greater maximal cardiac pumping capability and reserve than non-athletes. The study provides new evidence that resting measures of cardiac structure and function need to be considered with caution in interpretation of maximal cardiac performance.

Asymmetry of muscle strength in elite athletes Study aim: To determine muscle strength variables in elite judoists and wrestlers since thigh muscle strength and bilaterally balanced flexor-to-extensor ratio minimise injury risk and are desirable for achieving sport successes. Material and methods: Judoists, wrestlers and untrained subjects, 10 each, were subjected to isokinetic strength measurements of relative peak torques of knee flexor and extensor muscles on "Easy-Tech" dynamometer in concentric-concentric mode. Results: Mean relative peak muscle torques for knee flexors ranged from 1.14 ±0.27 (untrained) to 1.57 ±0.40 (judoists) N·m/kg and for knee extensors from 2.77 ± 0.34 (untrained) to 3.60 ± 0.64 (wrestlers) N·m/kg. The flexor-to-extensor ratios ranged from 39.3 ± 6.0 to 47.8 ± 10.8% and did not differ significantly between groups. Absolute right/left asymmetry for knee flexors ranged from 14.6 ± 10.4 to 17.4 ± 11.8% and was significantly (p<0.01) higher than for knee extensors (7.2 ± 6.8 to 8.6 ± 7.7%). All asymmetry indices were significant (p<0.01), no significant between group differences being detected. Conclusions: Implementing new training elements and modalities may improve the performance and prevent lateral asymmetry thus decreasing the risk of injuries.

Specific body composition and anthropometri- cal assessment as a part of morphological analysis should complement physiological profile of elite athletes. The analysis of the anaerobic performance shows that the handball players have greater alactic anaerobic and explosive power component, compared to the rowers in whom the anaerobic endurance and specific training have the greatest effect on the consumption of dominant metabolic substrate during the race.

Study results indicate a possible use of US in the diagnostics of fractures and monitoring of calcaneal healing.

Ultrasonography has not previously been used for studying fetal movements in precocial rodents. The objective of this study was to ultrasonographically determine the sequence of the appearance of basic movements in a guinea pig fetus. The research included eight guinea pig females carrying one fetus each. Fetal movements were observed for 10 minutes each day, from the 25 th to 38 th day of gestation. The time and sequence of the appearance of movements was observed as follows: whole body flexion (mean 27.6 SD ± 1.68), whole body extension (mean 28.1 SD ± 1.12), head flexion (mean 28.1 SD ± 1.80), head extension (mean 30.5 SD ± 2.67) forelimbs flexion (mean 30.5 SD ± 2.32), forelimbs extension (mean 30.7 SD ± 1.84), trunk rotation (mean 31.9 SD ± 2.23), forelimbs alternating flexion and extension (mean 32.1 SD ± 2.1), hind limbs extension (mean 32.2 SD ± 3.2), hind limbs flexion (mean 32.4 SD ± 3.16), and hind limbs alternating flexion and extension (mean 33.5 SD ± 2.39). The identical sequences of basic movement appearances in guinea pigs, sheep, and rats suggest that the rostrocaudal gradient of basic movement appearance could be a general developmental pattern in mammalian species.

A modified Wingate test of leg extension on a dynamometer in sedentary young men shows a correlation with the classic Wingate test only in parameters of peak power, and mean power and the second, the third and the last 5 s intervals. Because of that it should only be used for orientation, whereas for precise measurements of anaerobic capacity the classic Wingate test should be used.

The amplitude of the P300 wave, following exercise intensity at 75% of the maximum pulse (Pmax) (Fz 15.00+/-4.57, Cz 18.63+/-8.83 mV ) was statistically higher (p<0.05) than the amplitude of the P300 at rest (Fz 11.21+/-4.15 mV; (Cz 13.40+/-8.04 mV), at 60% (Fz 11.86+/-5.11 mV; Cz 14.54+/-8.06 mV) and at 90% of maximum pulse (Fz 13.26+/-4.73 mV; Cz 14.91+/-8.91 mV). There were no statistically significant differences (p>0.05) between amplitudes at 60% of Pmax and values obtained at rest and at 90% of Pmax. Also, no statistically significant differences were recorded (p>0.05) among the latencies of P300 recorded at rest (Fz 323.57+/-3.24 ms; Cz 323.57+/-13.24 ms) and at 60% of Pmax (Fz 321.14+/-22.38 ms; Cz 321.86+/-22.88 ms), at 75% of Pmax (Fz 321.50+/-16.67 ms; Cz 322.50+/-14.60 ms) and at 90% of Pmax (Fz 326.29+/-7.85 ms; Cz 325.43+/-7.63 ms). DISCUSSSION AND CONCLUSION: Physical activity has a positive impact on cognitive functions. At intermediate intensities, the amplitude of P300 increases, but at submaximal intensities it decreases to values obtained at rest. However, the latency of P300 did not show a statistically significant change after different intensities of exercise.