Scientists may have found a way to build bigger muscles — even without a costly gym membership.

University of Florida researchers report in the March print issue of the FASEB Journal that a family of protein transcription factors called Forkhead (or FoxO) plays a significant role in how skeletal muscle mass is regulated. They discovered that interfering with the factors’ activity prevents the muscle wasting often associated with cancer and sepsis, and could even promote muscle growth.

In their experiments, researcher Andrew R. Judge, Ph.D. from the Department of Physical Therapy at the University of Florida in Gainesville and his colleagues genetically inhibited the activity of FoxO in the skeletal muscle of healthy mice, septic mice, and cancerous mice.

They found a significant decrease in the loss of muscle mass in the cancer and sepsis groups. As a result of protein synthesis, inhibiting FoxO activity in the healthy mice caused an increase in muscle cell size.

“The loss of muscle mass is a major contributor to disease-related deaths,” Judge said in a press release. “FoxO proteins may provide a target for therapies aimed at reducing muscle wasting and thus improving the quality of life and survival rates for patients with many different diseases.”