Calf Imbalance
One of the cool things about the multi-sport watches these days is all the in built metrics. Garmin watches have the ability to tell you your foot ground contact time (GCT) and compare feet. For this Ironman athlete his balance was always off by 3-5%. This might not sound like much, but multiply this by thousands of steps and the pressure will certainly build up. For him, it felt like he had torn his calf and there was no chance he could run off the bike. Literally after his first adjustment his GCT was back within 0.5%, after a few weeks this stabilised and now he is consistently running well, feeling good, his GCT is almost always spot on and there has been absolutely zero calf “tears” or niggles.