When the hoof of a galloping horse hits the ground, the digital flexor tendon in its lower leg may stretch by 5% in length, a significant stretch for this 45 cm tendon. The tendon is elastic; most—but not all—of the energy stored in the stretch is returned, which allows for efficient locomotion. In an exercising horse, the tendon may reach a temperature of 46°C, much higher than the horse’s 38°C body temperature. How can you explain this temperature rise?