直立中の足踏み運動が下腿での水分貯留軽減に及ぼす効果について

抄録

Blood and tissue fluid are known to be retained at the lower leg when standing posture is maintained for a long period of time. In the current study, we examined the effects of intermittent stepping on blood and tissue fluid retention at this site. Electrical measurements assessed fluid status in the blood vessels and intracellular space in the lower leg muscles, using multi-frequency impedance (MIP). Lower leg circumference was obtained by measuring the triceps surae belly. Nine kinds of MIPs were used, ranging from 5 to 700 kHz. While participants kept an upright static posture for 30 minutes, the circumference and impedance (IP) was measured every five minutes, for a total of seven times. Stepping exercise was performed for a minute every time the upright static posture was measured. IP with a low frequency and continuous reduction in extracellular resistance was observed during upright posture; an increase in the lower leg circumference of 0.9 cm was observed. A statistically significant negative correlation was observed between the lower leg circumference and the extracellular resistance. On the other hand, the increase in circumference was reduced to 0.5 cm by intermittent stepping exercise, and the degree of reduction in extracellular resistance became milder than during standing upright. The data described here indicate that retention of tissue fluid at the lower leg and recovery of blood in a vein is enhanced by pumping of the lower leg muscles caused by stepping exercise.