自行车骑行过程中频率及生理节律对下肢肌电的影响研究

The Influencing Research About the Lower Limbs Muscles EMG Characteristics During Cycling at Different Pedaling Frequencies and Circadian Rhythm

通过在不同生理节律下改变踏蹬频率的骑行实验,获得了如下结论:①臀大肌、股二头肌在早晨的肌电爆发点比下午早,腓肠肌在早晨的肌电爆发点比下午晚,而胫骨前肌、股直肌的肌电爆发点与频率有关;股二头肌下午的肌电结束点比早晨早;股直肌及股二头肌的放电区间下午比早晨短.②频率增加引起臀大肌、股直肌、股二头肌、股外肌肌电爆发点、结束点近似同步前移,但频率增加却引起胫骨前肌爆发点前移而结束点延迟.③臀大肌、股外肌、胫骨前肌、腓肠肌放电区域随频率的增加而发生显著波动,当频率处于80～90r/min之间时,其放电区域较短,超出这个范围,则显著延长.

Some conclusions have been obtained through cycling experiment at different pedaling frequencies and circadian rhythm. ①Gluteus maximus （GM） and biceps femoris（BF） exhibited a earlier burst start phase in morning than afternoon. Gastrocnemius medialis （GAS） exhibited a later burst start in the morn- ing than in the afternoon. The burst start of brectus femoris （RF） and tibialis anterior （TA） had relationship with frequency and biceps femoris （BF） exhibited a earlier the burst end phase in the afternoon than in the morning. RF and BF exhibited a shorter activity range and working hours percentage in the afternoon than in the morning. ②An advanced Phase shifting approximately synchronously in both burst start and burst end has been observed in GM, RF, BF and VL following pedal rate increased, however,increasing the pedal rate led an advanced burst start phase and a delay burst end phase in TA. ③ Muscle activity range and working hours percentage in GM, VL, TA and GAS exhibited an obviously fluctuation as the pedal rate increased. When the frequency was in 80 - 90 r/min, GM, VL, TA and GAS activity ranges and working hours percentage were all shorter, go beyond this frequency, delayed markedly in activity range and work- ing hours pereentage.