The Real Deal about Fasted Cardio

Probably the most practiced technique for burning fat, the research points to the opposite results. According to this analysis of the research, 1)fasted training in general can lead to breakdown of protein tissue before adipose tissue 2) HIIT has been proven superior for fat loss, partly by cutting off blood supply to adipose tissue 3) fat loss is best determined over a 24hr period vs interval. There are quite a few studies quoted here but this was worth quoting: “showed that although lipolysis was suppressed by 22% in the fed state compared with the fasted state, fat oxidation remained similar between groups until 80–90 minutes of cycling. Only AFTER this point was a greater fat oxidation rate observed in fasted subjects. Conversely, during moderate-intensity cycling, fat oxidation was not different between trials at any time—this is despite a 20–25% reduction in lipolysis and plasma Free fatty acid concentration.” Basically, this says that fat burning was about the same in both fed/fasted groups until 80-90min! Also, any free fatty acids broken down during high intense exercise not oxidized for fuel can be re-esterified in fat cells, thus nullifying any benefits of lipolytic activity from fasting. Studies also show that a pre-training meal can increase training intensity, which can lead to more kcal burning, both during and after exercise. This can enhance overall fat burning. Bottom line: fasted cardio(steady state) doesn’t seem to have any more of a fat burning effect vs fed, and intensity of the exercise is more important to actual burning fat over 24hr period. Food for thought