Cardio sheds more fat mass than lifting alone, but body fat percentage ties

People trying to lose fat face a basic programming choice: lift weights, do cardio, or combine the two. Each approach has claimed advantages, with lifting defended for preserving muscle and cardio credited with burning more energy, while combined, or concurrent, training promises both at once. Few analyses have compared all three head to head in metabolically healthy adults. This review set out to do exactly that, and also to test whether programme duration, whether cardio and lifting fall on the same day, and whether matched workloads change the picture.

The authors systematically searched PubMed, SportDiscus and Web of Science for randomised controlled trials published between January 1980 and January 2023 comparing resistance, aerobic and concurrent training in healthy adults. Thirty-six studies with 1564 participants entered the review, and 31 were pooled after excluding studies with missing data. Primary outcomes were fat mass and body fat percentage; secondary outcomes were body mass and fat-free mass. Sub-analyses examined interventions shorter or longer than 10 weeks, same-day versus different-day concurrent training, and comparisons where workloads were equated between modes.

In programmes of at least 10 weeks, aerobic training outperformed resistance training for body mass, by 1.82 kg, and for fat mass, by 1.06 kg, though it preserved less fat-free mass, 0.88 kg less. Concurrent training removed 1.09 kg more fat mass than resistance training alone. Body fat percentage, however, did not differ between any of the modalities. In programmes under 10 weeks, no differences appeared at all. When workloads were matched, fat mass, body mass, body fat percentage and fat-free mass changes were all similar, and same-day versus different-day concurrent training performed alike.

The findings support combining cardio and lifting for fat loss: resistance work neither improved nor impeded fat mass reduction when incorporated into concurrent training, so nothing is sacrificed by keeping it. The workload-matched result is arguably the most interesting nuance, hinting that total work and programme duration, rather than the exercise mode itself, may drive the fat loss differences seen elsewhere. Open questions include how these patterns extend beyond metabolically healthy adults and over timeframes longer than the included trials.

This is a reason to think exercise mode matters less than commitment: over short periods no approach won, and with workloads matched no approach won either. Where differences did appear, they favoured programmes containing cardio for shedding absolute fat mass, while lifting alone lagged slightly and held onto more fat-free mass. For anyone wondering whether to schedule cardio and weights on the same day or split them across the week, the evidence here suggests it makes no meaningful difference.