Concurrent training order: strength before cardio provides a +11% boost to explosive strength.

Concurrent training order — this is a question that comes up in every conversation. Those who train twice a week have asked themselves this. Barbell first, then treadmill, or vice versa. Until recently, the answer was “whatever's convenient.” Now, the answer is more specific.

A 12-week RCT, 45 obese men (BMI ~30). Two concurrent training orders in the same session were compared: strength before cardio (CRE) and cardio before strength (CER). A third group was the control. Training was 3 times per week, 60-minute sessions: 30 minutes of strength + 30 minutes of cardio.

Result: VO2 max is not affected. Strength, explosive power, and muscular endurance are affected, and noticeably.

What did the study show about concurrent training order

Participants: 45 young men with obesity. No regular exercise for six months prior to the start. Strength training — 6 basic exercises (bench press, deadlift, squats, lateral raises, toe raises, bicep curls). Progression from 50% to 80% of 1RM over 12 weeks. Endurance training — running or exercise bike from 55% to 75% of maximum heart rate. Calorie intake and diet composition were controlled — there were no differences between the groups. In other words, this was not a case of “one group eating more protein”, but the pure effect of concurrent training order.

Both groups improved compared to the control. The question is, by how much.

Indicator	Strength → Cardio (CRE)	Cardio → Strength (CER)
VO₂max	+13.3%	+11.6%
Maximum strength	+21.8%	+15.0%
Explosive force	+28.2%	+17.2%
Muscular endurance	+26.7%	+17.0%
MVPA a day	+19 mins	+11.9 mins
Steps per day	+3488	+1580
Reduction in % fat	More	less

The biggest gap is in explosive power and muscular endurance. This is almost 1.5 times better than the same volume of work. The only difference is what came first.

The VO2max increase is almost identical, which confirms that concurrent training order does not “break” cardio adaptation. You can do strength first without losing the aerobic component.

Why does order matter at all

Concurrent training order is not a matter of comfort. It is a question of the metabolic state the muscle enters into when performing strength work.

Cardio before strength doesn't mean strength goes in “tired”. It means strength goes in a completely different metabolic state.

After 30 minutes of endurance exercise at 60–75% of maximum heart rate, the pH of the muscle changes. This is metabolic acidosis. Phosphate (Pi) and extracellular potassium (K⁺) accumulate. The sensitivity of muscle fibres to calcium decreases—and this is the “contract” signal transmitted from the nerve to the muscle. Plus, central fatigue sets in — the brain sends a weaker signal to repeat the action.

The practical implication is simple: you’ll do fewer reps on the same 80% from 1PM. Not because you’ve “lost strength”. It’s because the internal environment of the muscle is no longer the same.

If the force comes first, these mechanisms don't have time to engage. The volume of work done in the power part is greater. The adaptation is stronger.

The authors add another layer. When strength training precedes cardio, there are higher blood levels of free fatty acids, glycerol, and growth hormone before endurance work. This means that the subsequent cardio “burns” fat more effectively, hence the additional abdominal fat loss in the CRE group.

How does this affect body composition

Concurrent training itself changes body composition – dozens of studies have shown this. But the order of exercises changes specifically which ones disappears.

In the CRE group, the percentage of body fat decreased further. Most importantly, visceral (abdominal) fat: the fat around the internal organs. This is linked to an increased risk of diabetes, hypertension, and cardiovascular disease. This is not an aesthetic difference. It is a difference in metabolic risk one or two years after the intervention.

Bone mineral density increased equally in both groups — bone requires more than 12 weeks to show a difference in order.

What cyclists and runners should do with this

Last week There was an article here about a study in which cyclists were made to do strength training at 70% of their maximum capacity — and their VO₂max increased by 61%. That analysis concluded with the statement that “heavy strength training is necessary”. This study adds to that: if everything is done in a single session — strength training first, then cycling.

The logic is simple: a muscle fibre should not enter the force phase with a depleted calcium transport system. Otherwise, even a properly prescribed heavy workout on the 70-80% will yield poorer results than it could have.

When concurrent training order is not critical

If your sole aim is aerobic fitness (VO2max, cardiovascular endurance), the order doesn't matter. Both groups in the study saw virtually identical gains.

If strength training and cardio are done on different days, the order is not an issue at all. It only becomes relevant within a single session. For people with limited time, this is the typical scenario.

And also: the study was conducted on young men with obesity, with no training experience. Extrapolation to highly trained athletes should be done with caution. In their case, the interference effect mechanism might work slightly differently due to adaptation.

Practical steps

If the training is combined into one session, the structure looks like this:

1. 10-minute warm-up — joints, mobility, light cardio up to 50% of maximum heart rate
2. Strength training: 25–30 mins — basic exercises with progression to 70–80% of 1RM, 3 sets, 60–90-second rest periods
3. Endurance session: 25–30 mins — running, exercise bike, rowing, with intensity increasing to 70–75% of maximum heart rate
4. 5-min warm-down — stretching of working muscles

Total duration is 60-75 minutes. If time is even shorter, reduce the endurance part, not the strength part. Strength is what gives the main advantage of concurrent training order.

If training is on different days, the concurrent training order is not an issue. Separating cardio and strength by at least 6-8 hours already removes most interference. Better still is 24 hours.

One-sentence conclusion

For the same amount of work, concurrent training in a “strength before cardio” order yields approximately 11 percentage points greater explosive power gains. This is the best that can be achieved simply by reversing the order of exercises.

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Sources

• Li Z, Gong T, Ren Z, et al. Impact of sequence in concurrent training on physical activity, body composition, and fitness in obese young males: A 12-week randomised controlled trial. Journal of Exercise Science and Fitness. 2025;23(2):112-121. DOI: 10.1016/j.jesf.2025.02.001
• Gao J, Yu L. Effects of concurrent training sequence on VO2max and lower limb strength performance: a systematic review and meta-analysis. Frontiers in Physiology. 2023;14. DOI: 10.3389/fphys.2023.1072679