Ice baths, also known as cold water immersion, have been studied for their effects on growth hormone (GH) and insulin-like growth factor 1 (IGF-1) levels, as well as muscle hypertrophy.
One study, published in the Journal of Physiology in 2008, found that a 10-minute immersion in cold water (14°C) significantly decreased GH and IGF-1 levels in healthy men. This decrease in GH and IGF-1 levels may impede muscle growth and repair, potentially reducing the effects of muscular hypertrophy.
Another study, published in the Journal of Science and Medicine in Sport in 2011, found that 10-minute cold water immersions post-exercise significantly decreased muscle soreness and inflammation, but also decreased muscle strength and power. This suggests that cold water immersion may have a negative effect on muscle recovery and growth.
A study published in the Journal of Applied Physiology in 2016, found that cold water immersion decreased muscle protein synthesis which is an important process for muscle growth, this effect may be related to the decrease in GH and IGF-1 levels observed in previous studies.
It is also worth noting that there is some evidence that the benefits of cold water immersion may be specific to the type and intensity of exercise being performed. For example, a study published in the Journal of Strength and Conditioning Research in 2013 found that cold water immersion after high-intensity interval training had no effect on muscle strength or power, but did decrease muscle soreness.
In conclusion, while cold water immersion may have some benefits for reducing muscle soreness and inflammation, it may also have negative effects on muscle growth and recovery. The decrease in GH and IGF-1 levels observed in some studies may impede muscle growth and repair, potentially reducing the effects of muscular hypertrophy.
If your goal is to put on muscle mass or need the muscle repair for recovery you’ll need to counteract these effects, if you’re taking an ice bath make sure it’s 24 hours after your last hard session so your muscles have had time to recover fully before enjoying the anti-inflammatory and soreness reducing effects of an ice bath.