Cardio vs Weights vs Both: Which Burns More Fat?
A massive analysis reveals the ultimate fat loss routine—and why mixing workouts gets results.
So, what’s better for fat loss, lifting weights, or cardio? It’s an argument as old as time, and one every lifter asks now and then. This systematic review and meta-analysis dives into whether resistance, aerobic, or a combination (concurrent training) gets you leaner, faster, and what that means for your gym routine.
PMID: 40405489
Key Points
Aim
To compare the impact of resistance training (RT), aerobic training (AT), and concurrent training (CT: both resistance and aerobic on the same day) on body fat loss, body mass, fat-free mass (FFM), and body fat percentage in healthy adults.
Methods
Design: Systematic review and meta-analysis of 36 randomised controlled trials (RCTs) published between 1980 and January 2023.
Participants: 1,564 healthy adults (18+), metabolically healthy, untrained and trained, both male and female.
Interventions:
RT: Weights/machines
AT: Cardio (run, bike, step, etc.)
CT: Combination within the same week (same-day or different-day protocols)
Outcomes: Fat mass, body fat percentage, body mass, and FFM (muscle/non-fat mass)
Additional Analyses: Effects of program duration (<10 weeks vs ≥10 weeks), timing of CT (same-day vs different-day), and when session workloads were matched for total energy used1.
Results
Fat Loss & Body Weight
Aerobic (AT) and Concurrent Training (CT) were superior to Resistance Training (RT) alone for absolute fat mass loss.
AT outperformed RT for fat mass loss (mean difference −1.06kg) and body weight (mean difference −1.82kg) for programs ≥10 weeks.
CT also reduced more fat mass than RT (mean difference −1.09kg).
There was no significant difference between AT and CT for fat mass loss—both were equally effective.
Body Fat Percentage: No meaningful difference among AT, RT, and CT for % body fat lost.
Short Programs (<10 weeks): No differences among AT, RT, or CT in any outcome—if your plan is short, just getting active matters more than the type.
Muscle Mass (Fat-Free Mass)
RT preserves muscle mass the best. AT resulted in less fat-free mass retention compared to RT.
CT landed in-between AT and RT—not significantly different from either for FFM changes.
If maximal muscle retention is your goal during fat loss, some resistance work is necessary.
Workload Matters (Calorie Control)
When workouts were matched for energy used or duration, differences between RT, AT, and CT disappeared. That means the amount of work (calories) is as important as the type of work.
Scheduling (Same-Day vs Different-Day for CT)
Whether you combine weights and cardio on the same day or different days during the week does not meaningfully affect fat loss or muscle retention.
