"Well, my trainer wants me to do fasting cardio at least three days a week..." is a common comment I hear frequently. The theory for the uninitiated is that one would burn fat resulting in greater fat loss versus the typical muscle/fat loss that comes from changing body composition.
The Journal of the International Sports Society of Sports Nutrition recently published an article to bring additional clarity on the topic. This article focuses on twenty women who are to follow a reduced calorie diet. They either do cardio in a fasting or fed state.
The researchers found that "[b]oth groups showed a significant loss of weight (P = 0.0005) and fat mass (P = 0.02) from baseline, but no significant between-group differences were noted in any outcome measure. These findings indicate that body composition changes associated with aerobic exercise in conjunction with a hypocaloric diet are similar regardless whether or not an individual is fasted prior to training" (Schoenfeld, et al, 2014).
The takeaway? Keep encouraging a reduced calorie diet with physical activity to see results.
Check out the full article here.
Gina Volsko RDN, LD is the SCAN Blog Coordinator and writes on her own nutrition blog, Sport2Fork. E-mail her at firstname.lastname@example.org if you're interesting in joining the SCAN bloggers.