A study has found that hot baths could boost your running performance, as long-term heat exposure could trigger physiological changes similar to those seen at altitude training at altitude. The study recruited a group of well-trained endurance runners who underwent five hot baths per week for five weeks. The baths were not high-tech laboratory grade equipment, but standard home bathtubs were used to maintain the water temperature at 40°C and warm water added when needed. The researchers found that after five weeks of regular hot baths, their red blood cell volume and heart structure significantly increased, allowing them to produce more oxygen-carrying cells in their bloodstream. These gains were found without increasing training intensity or mileage. The implications implications for runners and coaches, as this approach is relatively accessible and could allow for more equitable access to performance-enhancing training strategies. However, there are limitations as heat exposure can increase risk of dehydration and heat illness.