Hot muscle growth

Muscle & Fitness, August, 2006 by Tim Scheett

You train consistently day in and day out in an effort to gain as much muscle mass as possible. If you're really serious about bodybuilding, you've probably tried every training program imaginable as well as every supplement on the market. But what if we told you that gaining more muscle mass may be as simple as exposing yourself to heat?

According to new research from Japan, heat exposure may be just the thing to push your muscle growth to the next level. Scientists from the St. Marianna University School of Medicine (Kawasaka) exposed rats to a heat chamber set at 105 degrees F for one hour every day for two weeks. They measured the weight of the rats' soleus (calf) muscles and their total bodyweight after the first seven days and again at the end of the 14-day experiment, then compared them to a control group that wasn't exposed to heat. The researchers discovered that after just seven days of exposure, the muscles of the heated rats were significantly heavier than those of the control group. Total bodyweights in the heat-exposed rats were also 5% heavier at the end of the two-week study.

Thermal Science

Scientists analyzed the rats' muscles to determine what may be responsible for the heat-induced muscle growth. Specific proteins called heat-shock proteins are released when the body is exposed to heat. These proteins appear to alter calcium levels in muscles, which signal another protein (calcineurin) to activate the processes of protein synthesis (growth) in muscle cells. The conclusion: Heat-shock proteins seem to cause the increased muscle growth. Researchers suggest that these results strongly indicate that heat exposure may be a potential technique for inciting muscle growth.

MUSCLE ON FIRE

To try optimizing muscle growth with heat exposure, consider using a sauna or hot tub. Health experts recommended that you limit your time in a sauna or hot tub to 20 minutes. You can also get the same effect from a hot bath. Be sure to use heat exposure only after you work out--never before.

M&F Senior Science Editor JIM STOPPANI, PHD

BY TIM SCHEETT, PHD