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Objectives: To determine the effect of leg immersion in cold water after stretch-shortening exercise (SSE) on the time-course of indirect indicators of exercise-induced muscle damage (EIMD). Methods: Twenty healthy untrained men twice performed SSE consisting of 100 drop jumps (DJs) from 0.75 m height performed with maximal intensity with an interval of 20 s between the jumps. DJs were performed with counter-movement to 90 degrees angle in the knee and with immediate maximal rebounds. After SSE the subject's legs immediately, as well as after 4 h, 8 h and 24 h, were immersed into a bath filled with water at 15 ± 1 • C. Quadriceps muscle voluntary contraction force (MVCF) and force evoked by electrostimulation (ESF) at different frequencies and at different muscle length, jump height (H), muscle soreness and creatine kinase (CK) activity in the blood were measured before SSE, immediately after SSE and within 72 h of recovery. Results: After stretch-shortening exercise MVCF, ESF and H were significantly (P < 0.001) decreased and were not restored even after 72 h in the group that did not receive the cooling. Within 24-48 h after SSE the subjects felt great muscle pain and CK activity in their blood was increased (P < 0.001). The cooling significantly accelerated the disappearance of all these indicators, except for low-frequency fatigue, but only within 24-72 h after SSE. Conclusion: Cold water immersion after SSE accelerates the disappearance of the majority of indirect indicators of EIMD.

Background and Objective. Many studies have suggested that each hand has a different special talent; however, there is a lack of data in the area of goal-directed bimanual hand coordination and its dependence on gender. The aim of this paper was to investigate gender-dependent bimanual speed-accuracy task performance. Material and Methods. Twelve healthy young males and twelve healthy young females (all righthanded) performed protractile movements with both arms simultaneously by pushing joysticks toward two targets as quickly and accurately as possible. Results. Though no significant difference was observed in the reaction time during a unimanual speed-accuracy task between the left and right hands as well as men and women, during a bimanual task, the reaction time of both the hands was significantly longer in women than men. There was no significant difference in the velocity of both the hands during a bimanual speed-accuracy task between men and women, while the accuracy of the left hand was significantly greater in men than women. There was no significant difference in intraindividual variability in the reaction time, maximal velocity, and path of movement between men and women as well as the left and right hands, but variability in the average velocity of the right hand both in women and men was significantly greater compared with their left hand. Conclusions. Whereas people typically look at the target location for a reaching movement, it is possible that two objects are simultaneously fixated.

The aim of the present study was to establish the influence of muscle heating and cooling on knee flexors and extensors during fatiguing exercise. The participants of the study were 10 healthy males aged 19–23 years. The participants of the study were tested with the isokinetic dynamometer. Control measurements were done before the load as well as 10 min, 30 min, 60 min, and 24 h after the load. The participants performed concentric exercise bouts: 50 knee extensions and flexions at the fixed speed of 180°/s, when femoral muscles before concentric load were of normal temperature, were heated or cooled. Creatine kinase activity in blood serum was estimated 1 h before the load and 24 h after it. Internal temperature of the muscle quadriceps femoris after muscle heating for 45 min increased to 39.5±0.2°C (P<0.001) and after muscle cooling for 30 min decreased to 32.5±0.3°C (P<0.05) as compared to baseline temperature (before heating – 36.9±0.1°C, before cooling – 36.8±0.2°C). Creatine kinase activity in blood serum 24 h after concentric load was significantly increased as compared to control values. Passive muscle warming increased muscle contraction force of knee extensors, but did not cause any changes either in the rate of muscle fatigue or in the rate of muscle recovery. Muscle cooling did not decrease muscle contraction force and did not increase muscle fatigue resistance. The findings of this study showed that both, muscle warming and muscle cooling, brought about a decrease in an indirect parameter of muscle damage – the amount of creatine kinase 24 h after concentric load.

This pilot study gives evidence on the effect of low frequency 2-10 Hz vibration on young physically inactive subjects and associations with blood flow in limbs. For the study purposes, low frequency 2-10 Hz vibration was applied for the subjects in the lying position, and a special device, patented at Kaunas University of Technology, was used to generate low frequency vibrations. Altered temperatures in feet were measured with a thermovisual camera, which records thermal changes. Thermovisual measurement was performed in a warm room (20-21 °C). The entire procedure lasted 45 minutes. Thermovisual measurement was performed 15 minutes before vibration, 15 minutes during vibration and 15 minutes after vibration. For temperature analysis, 2 points on the subjects' feet were chosen: the central point on the foot where the highest temperature was taken and the peripheral point on the foot where the lowest temperature was measured. Heart rate variability was measured by the Elite HRV programme. The data analysis of temperature in both the central and the peripheral points of the foot under low frequency 2-10 Hz vibration showed insignificant changes in temperature and blood flow; however, the differences determined were insignificant. The assessment of heart rate variability demonstrated that there were statistically significant differences before, during and after vibration. A tendency of the heart rate to increase shows that the heart also reacts to any changes when peripheral blood flow in feet is affected. A reverse dependence was determined: low temperature in the foot increases heart rate variability and, vice versa, increasing temperature decreases heart rate variability. It would be expedient and useful to conduct results with those of healthy subjects.