Claim check

Does cardio kill your muscle gains?

An updated meta-analysis of 43 studies found no loss of muscle growth or maximal strength from adding cardio, with one exception: explosive power.

“Cardio kills your gains.”

The claim, as it’s posted. Seen on bodybuilding forums, gym TikTok, and lifting subreddits.

Our verdict: Doesn’t hold up

Verdict: Doesn’t hold up

Adding cardio to lifting does not reduce muscle growth or maximal strength on average, though same-session cardio can blunt explosive power.

Checked
Oct 2026
Sources
5
Newest
2026

The key numbers

  • 43studies

    Studies in the 2022 meta-analysis

    Source 1

  • −0.01SMD

    Difference in muscle growth, cardio plus lifting compared with lifting alone

    Source 1

  • −0.28SMD

    Difference in explosive strength

    Source 1

  • 150–300minutes

    Weekly moderate activity recommended by WHO

    Source 4

What the evidence says, in six sentences

Our own summary of the sources listed at the bottom of this page.

  1. The worry has some basis, since an influential 2012 meta-analysis linked running, and more frequent or longer cardio sessions, to smaller gains in muscle size and strength.
  2. The claim goes too far, because an updated 2022 meta-analysis of 43 studies found that adding aerobic training did not reduce muscle growth or maximal strength compared with lifting alone.
  3. The pooled differences were -0.01 for muscle size and -0.06 for maximal strength, both close to zero, while explosive strength was modestly lower at -0.28, with an interval from -0.48 to -0.08.
  4. The power penalty matters most for jumpers, sprinters, and other athletes who rely on speed, and it was larger when cardio and lifting happened in the same session.
  5. For most people, doing both is the better plan, matching WHO advice of 150 to 300 minutes of moderate activity a week plus muscle strengthening on two or more days.
  6. Because the 2012 analysis tied interference to more frequent and longer cardio, people doing very high endurance volumes should not assume the average result fully applies to them.

The numbers, drawn

Every chart is drawn from the published estimates. Bars and intervals show the uncertainty; a dashed line marks no difference.

Figure 1Cardio plus lifting compared with lifting alonestandardized mean difference (negative = smaller gains with cardio)
  • Muscle growth2022 meta-analysis of 43 studies; interval as reported−0.01 (−0.16 to 0.18)
  • Maximal strength2022 meta-analysis−0.06 (−0.20 to 0.09)
  • Explosive strength2022 meta-analysis; larger when done in the same session−0.28 (−0.48 to −0.08)
  • Lower-body strength with HIIT added2018 meta-analysis; reported as -0.248, p = 0.049; interval not given in abstract−0.25 (no interval)
  • Lower-body strength with sprint intervals added2026 meta-analysis of 9 studies; p = 0.94; interval not given in abstract0.01 (no interval)

Pooled differences between people who added cardio to lifting and people who only lifted, with 95% confidence intervals where reported. Muscle growth and maximal strength showed no penalty; explosive strength did.

Sources: 1Sports Medicine, 2022 3Journal of Sports Sciences, 2018 5International Journal of Sports Medicine, 2026

Figure 2Muscle growth effect sizes in the 2012 meta-analysiseffect size (gain within each type of program)
  • Strength training only1.23
  • Strength plus endurance training0.85
  • Endurance training only0.27

The older 2012 analysis of 21 studies found somewhat smaller growth in combined programs, mostly tied to running and to more frequent or longer cardio. Source: Wilson 2012, Journal of Strength and Conditioning Research.

Source: 2Journal of Strength and Conditioning Research, 2012

Figure 3The claim and the evidenceSide by side

The claim

  • Any cardio eats into muscle growth
  • Lifters should skip cardio
  • The effect is the same for everyone

The evidence

  • No average loss of muscle growth or maximal strength
  • Guidelines recommend both cardio and strength work
  • Explosive power took a modest hit, mainly same-session

A side-by-side summary of the cardio myth and pooled trial results. Sources: Schumann 2022 and WHO 2020.

What to do with this

  • Keep doing cardio; on average it does not cost you muscle or maximal strength.
  • If explosive power matters for your sport, separate cardio and lifting by several hours when you can.
  • Build up very high cardio volumes gradually and watch whether your lifts stall.

Key terms

Concurrent training
Doing aerobic (cardio) and strength training in the same program.
Interference effect
The idea that endurance training blunts the gains from strength training.
Hypertrophy
Growth in muscle size.
Standardized mean difference
An effect size that lets studies using different measures be combined; about 0.2 is small.
Explosive strength
How quickly you can produce force, as in jumping or sprinting.

What we read 5

  1. 1Compatibility of Concurrent Aerobic and Strength Training for Skeletal Muscle Size and Function: An Updated Systematic Review and Meta-AnalysisSports Medicine, 2022
  2. 2Concurrent training: a meta-analysis examining interference of aerobic and resistance exercisesJournal of Strength and Conditioning Research, 2012
  3. 3The compatibility of concurrent high intensity interval training and resistance training for muscular strength and hypertrophy: a systematic review and meta-analysisJournal of Sports Sciences, 2018
  4. 4World Health Organization 2020 guidelines on physical activity and sedentary behaviourBritish Journal of Sports Medicine, 2020
  5. 5Does Sprint Interval Training Cause Interference in Concurrent Training? A Meta-Analysis StudyInternational Journal of Sports Medicine, 2026

Written and drawn by go4 with AI assistance (Claude, by Anthropic) after reading these sources, and checked against them. No text or figures were copied. Checked Oct 2026.

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