Influence of different training patterns on the biomechanical performance of the terminal region of the Achilles tendon in rabbits

Objective  To investigate the effects of the different training patterns on the biomechanical performance of the terminal region of the Achilles tendon for providing a scientific basis for improving the ability of anti-stress and preventing injury in military physical training. Methods  Fifty Japanese white rabbits were randomly assigned to four groups: control ( n =5), running (running training on the running table, n =15), jump (jump training by electric shock, n =15), and cycle training (run and jump cycle, n =15). The animals in the control group were sacrificed at the start of the experiment. For the other training groups, three rabbits were sacrificed randomly in the second, third, fourth, sixth, and eighth week, respectively. The terminal regions of the Achilles tendons in both sides were identified to determine the biomechanics. Results  At the sixth week, the limit stress and the elastic modulus reached the highest in the running group, and then reduced with the increase in training time. Meanwhile, in the jump group, the limit stress and elastic modulus reached the peak at the fourth week, and then decreased gradually. In the eighth week, no significant difference was observed when the groups were compared with the control group. In the cycle group, the limit stress and elastic modulus increased gradually with the increase in training time, reaching the peak value in the eighth week, and no decline was recorded during the training period. Conclusions  Running training can slowly improve the biomechanical performance of the tissues in the terminal region of the Achilles tendon, whereas jump training can rapidly increase it, although long-term excessive training will reduce the anti-injury ability. Meanwhile, cycle training can improve the biomechanical performance of the tissues in the terminal region of the Achilles tendon, enabling it to withstand more stress and thus its anti-injury ability is enhanced.