I have seen many people going a little overboard with their cardio regimes the past few weeks, worrying about their inactivity potentially leading to fat gain. Too much cardio however, (especially HIT cardio) may in fact jeopardize retention of lean mass as these studies👇🏽show.
Willis et al 2012, compared aerobic training (AT), resistance training (RT), and a combination of the two (AT/RT) to determine the optimal mode of exercise during fat loss.
✔The AT and AT/RT groups ⬇️ decreased total body mass & fat mass by a greater amount compared to RT (P < 0.05), but they were not significantly different from each other.
✔RT and AT/RT ⬆️ was able to increase lean body mass more than AT (P < 0.05).
✔RT and RT/AT both led to equal amounts of total body weight loss & fat loss %, however it required more time investment.
✔RT led to significantly greater retention of LBM compared to AT.
Focusing on resistance training in combination with some lower intensity cardio seems to be a smarter strategy for fat loss while also providing the added benefit of helping to retain lean mass compared with either exercise modality on its own.
If increasing muscle mass & strength is your main goal, a program that includes RT is key.
Something to note, studies have shown it is possible for overweight individuals to lose a far greater % of their body weight from fat while dieting, the mechanism is thought to be related to the excess energy availability from adipose tissue.
If aerobic training increases the ratio of weight loss in an unfavorable direction even for obese individuals as shown in this study, this raises even greater concerns for individuals with low body fat mass (competitors)!