Effects of tendon elastic energy and electromyographic activity pattern on jumping height and pre-stretch augmentation during jumps with different pre-stretch intensity.

The present study aimed to investigate the effects of tendon elastic energy and electromyographic activity patterns (ratio of pre-landing to concentric: mEMG PLA/CON; ratio of eccentric to concentric; mEMG ECC/CON) on jump performance. Twenty-nine males performed five kinds of unilateral jumps using only ankle joint (no-countermovement jump: noCMJ; countermovement jump: CMJ; drop jumps at 10, 20 and 30 cm drop height: DJ10, DJ20 and DJ30). Jumping height, pre-stretch augmentation and electromyographic activity of the plantar flexor muscles were measured.

Determinants of joint stiffness and jumping height during drop jump.

The present study aimed to examine the effects of muscle-tendon mechanical properties and electromyographic activity on joint stiffness and jumping height and to explore the determinants of joint stiffness and jumping height. Twenty-nine males performed unilateral drop jumps at three drop heights (10, 20, and 30 cm) using only the ankle joint on the sledge apparatus. Ankle joint stiffness, jumping height, and electromyographic activity of the plantar flexor muscles were measured during drop jumps.

Effect of relaxation time on hysteresis of human tendon .

Objectives: The purpose of this study was to investigate the effect of relaxation time on tendon hysteresis.

Methods: Subjects exerted isometric plantar flexion torque from rest to maximal voluntary isometric contractions within around 0.5 s, followed by relaxation with six different times (0.

Changes in tendon blood circulation and heart rate variability after intermittent compression to patellar and Achilles tendons.

Background: The purpose of this study was to compare changes in tendon blood circulation and heart rate variability after intermittent compression to the patellar and Achilles tendons.

Methods: Before the intermittent compression to tendons (3 min) and the recovery period (40 min), the blood volume and oxygen saturation of the patellar and Achilles tendons were measured using red laser lights. In addition, heart rate and ratio of low-frequency to high-frequency components of heart rate variability were measured.