[Reactions of the cardiopulmonary and the motor system in work with medium-sized muscles]. / Reaktionen des kardiopulmonalen und des motorischen Systems bei Arbeit mit mittleren Muskelmassen.

Three groups of untrained males and two groups of untrained women (aged 20...49 years) carried out one-arm cranking with defined loads. All derived parameters of the cardiopulmonary and motor systems showed a load-dependent behaviour. There were sex-differences in heart rate, oxygen uptake and iEMG. The physical endurance limit was determined by 10 watts for males and 5 watts for women.

[The effect of increased environmental temperature on the behavior of physiologic parameters in bicycle ergometry within the scope of the physical endurance limit]. / Einfluss erhöhter Umgebungstemperatur auf das Verhalten physiologischer Parameter bei Fahrradergometerarbeit im Bereich der physischen Dauerleistungsgrenze.

For determination of the endurance limit range, 8 healthy male probands aged between 20 and 26 years loads had carried out for one hour on a bicycle ergometer at an ambient temperature of +20 degrees C, +28 degrees C and +35 degrees C. Staying in an ambient temperature of 35 degrees C leads to a decrease in the physical endurance limit in an order of magnitude of 10 W. At 20 degrees C, in the endurance range the following values result (mean +/- s): load 68+/- 10.3 W, heart rate 113.6 +/- 5.8 beats per min., net heart rate 31.8 +/- 2.4 beats per min., oxygen uptake 1340 +/- 170 ml per min., auditory canal temperature 36.5 +/- 0.24 degrees C, sweat rate 275 +/- 143 g. At 35 degrees C, the endurance limit is attained at the following values: 57 +/- 10.6 W, heart rate 125 +/- 11.8 beats per min., net heart rate 27.4 +/- 3.6 beats per min., oxygen uptake 1210 +/- 130 ml per min., auditory canal temperature 37.2 +/- 0.3 degrees C, sweat rate 577 +/- 96 g.

Changes of the EMG and its relationship to the cardiopulmonary parameters during two-arm cranking of disabled men.

During two-arm cranking in 5 groups of men (able-bodied and leg-disabled with different states of training; wheelchair-dependents with basket-ball training) the behaviour of parameters of the motor and cardiopulmonary system (iEMG, heart rate, oxygen uptake) was investigated. On the basis of stepwise increasing physical work up to exhaustion the group of swimtrained leg-disabled men showed the highest physical working capacity. The lowest physical fitness was found in wheelchair-dependent men.

Sex- and age-related behaviour of the integrated EMG during one-arm cranking.

There are load-dependent increases in the bioelectrical activity (iEMG) of muscles of the shoulder and the right upper extremity and selected parameters of the cardiopulmonary system. At comparable loads the amplitudes of the EMG were higher in the group of men than in the group of women. The iEMG values were found to be higher in the younger group of women than in the older one. The higher values of iEMG of the younger women corresponded to a higher oxygen uptake and higher heart rate as well as to a lower physical endurance. The physical endurance limit (derived from behaviour of the EMG) was estimated at 5 watts (women) and 10 watts (men).

[Reproducibility of blood-flow measurement in the human forehead skin using thermodynamic probes]. / Untersuchungen über die Reproduzierbarkeit von Durchblutungsmessungen an der menschlichen Stirnhaut mittels Wärmeleitsonden

The reproducibility (test-retest-reliability) of the forehead skin blood flow (method: fluvography or heat clearance) was tested by means of determination of the intraclass correlation coefficient. Defined changes of skin blood flow may be caused by loading a heat flow probe with weights; this was done in the range from 20 p to 500 p both in an ascending and a descending manner. A good reproducibility of results was reached in all repeated measurements made at intervals of one or several days. The correlation coefficient increases with increasing loads (r = 0.471 at a loading of 20 p; r = 0.813 at a load of 500 p).

[Effect of experimentally induced changes in blood flow on the heat and electrical conductivity of the skin]. / Einfluss experimentell ausgelöster Durchblutungsnderungen auf die Wärmeleitzahl der Haut und die elektrische Leitfähigkeit des Gewebes

This paper reports on the influence of experimentally induced changes in blood flow in upper extremities on both electrical resistance (1100 Hz; 30 kHz) and heat conductivity of the skin in 19 healthy adults. Exsanguination (ESMARCH bandage) caused a small decrease in resistance with recovery of the blood flow. Both changed of skin resistance and resting values of skin resistance have shown sex-related differences. The changes of heat conductivity are higher as compared to values of skin resistance. The results are discussed and compared with data from the literature.