Cardio and lifting: order, timing and how much

Plenty of people who lift also run, ride or row, and most of them have heard that cardio "kills gains." Doing both has a name in sport science, concurrent training, and so does the worry: the interference effect, the idea that endurance work holds back the strength you'd build from lifting alone.¹

There's more research on this than most people expect, and it's calmer than the warning. This page is about what cardio does to your lifting: before or after, same day or separate days, how big the effect is, how much cardio fits beside a lifting plan, and whether the kind matters. It's about training, not the scale. If your question is really about weight, walking and steps and why you can't lose fat are the pages for that.

Cardio before or after lifting?

If strength is the priority, lift first. A 2018 meta-analysis pooled ten studies, 245 people in all, that compared the two orders inside the same session for five weeks or more. Lifting first improved lower-body one-rep max (a squat, leg press or leg extension) by about 7 percentage points more than cardio first.¹ The order made no difference to leg muscle size, to strength in a held contraction, or to aerobic fitness.¹ A second meta-analysis landed in the same place: about 4 kilograms more on a lower-body one-rep max when strength training came first, and no difference in aerobic capacity.²

Part of the reason is simple: cardio first means your lifting starts tired. A 2022 meta-analysis of 15 studies in trained men found that a bout of aerobic exercise caused a moderate drop in leg strength measured within fifteen minutes afterwards, and a large drop after sessions longer than thirty minutes, though the gap between shorter and longer sessions wasn't statistically clear.³

Two things the order doesn't change. Aerobic fitness improved about the same either way,^1,2 so if your cardio is the priority, doing it first is a fair trade. And a few easy minutes on a bike to warm up isn't what these studies tested: their cardio was a real session, 18 to 50 minutes in the studies that gave a time.¹ Nor are a few easy minutes after lifting: that's a cool-down.

Same day or separate days?

It depends mostly on how trained you are. A 2021 meta-analysis of 27 studies looked at leg press and squat one-rep max in three groups:⁴

• Untrained: adding cardio made no difference to strength gains (effect size 0.03).⁴
• Moderately trained (active, but not on a structured program): a small dip that wasn't statistically clear (−0.20).⁴
• Trained (on a structured program for at least three months): a small cost (−0.35), and it showed up only when the cardio and lifting were less than twenty minutes apart (−0.66, moderate). More than two hours apart, it was close to nothing (−0.10).⁴

The authors' advice for untrained and moderately trained people is that a combined program "can be based on more practical considerations or personal preferences."⁴ They also note that the same-session result in trained people rested largely on two interventions from one study, so it needs confirming.⁴ (For scale: researchers usually read an effect size of about 0.2 as small, 0.5 as moderate and 0.8 as large.⁴)

A larger 2022 review of 43 studies found the same timing pattern for one quality: explosive strength, measured mostly as jump height and fast force. Its gains took a bigger hit when cardio and lifting shared a session than when they were at least three hours apart.⁵ For muscle size and maximal strength, it made no difference whether people trained in the same session, on the same day or on different days.⁵

So, in practice:

• New, returning or training for general fitness: do whatever fits your week. Same session (lift first), same day, or separate days.
• Trained and chasing a bigger squat or leg press: keep cardio more than two hours away from lifting, or put it on another day.
• Your sport depends on jumping or explosive power: at least three hours apart, or separate days.

Cardio on the days you don't lift is fine, as long as it doesn't leave you too tired for the next session. Rest days covers what those days can look like.

The interference effect: how big is it?

The first big meta-analysis, in 2012, pooled 21 studies. People who did both gained muscle and strength too, with somewhat smaller average effect sizes than lifting alone: 0.85 against 1.23 for muscle growth, and 1.44 against 1.76 for strength.⁶ Power was the clearest gap, 0.55 against 0.91, a statistically significant difference.⁶ Running alongside lifting, but not cycling, significantly reduced both muscle growth and strength, and more frequent and longer cardio went with smaller gains.⁶

The 2022 update, with 43 studies and 1,090 people, found something calmer. Compared with lifting alone, adding aerobic training made no detectable difference to maximal strength (−0.06) or muscle size (−0.01), and cost a small amount of explosive strength (−0.28).⁵ It did not confirm the 2012 link between more cardio and less muscle growth.⁵ The authors called the overall risk of interference "rather low" and concluded that most people, recreational athletes included, can enjoy the benefits of doing both.⁵

One finer measure points the other way. A 2022 meta-analysis of 15 studies that measured individual muscle fibers found a small negative effect of concurrent training on fiber growth (−0.23), which, its authors note, doesn't necessarily show up as a difference in whole-muscle size.⁷

The honest summary: for most people, the cost to muscle size and maximal strength is small or nothing. It grows when you're well trained, when the cardio comes right before or right after lifting, and when the goal is explosive power.

How much cardio alongside a lifting plan?

The World Health Organization's guideline for adults is 150 to 300 minutes of moderate aerobic activity a week, or 75 to 150 minutes of vigorous activity, plus muscle-strengthening work on two or more days.⁸ That's both halves, not one or the other. The 2020 guidelines also dropped the old rule that activity only counts in bouts of ten minutes or more.⁸

Two ways to fit 150 minutes of moderate cardio beside three lifting days:

How often you do it matters less than you'd think. In the 2022 review, the comparison with lifting alone came out the same whether people did about four combined sessions a week or about six.⁵ The 2012 analysis is the reason to keep an eye on it anyway: there, more and longer cardio went with smaller gains.⁶ If your lifts stall while your cardio keeps climbing, the cardio is the first thing to look at. And if 150 minutes isn't realistic yet, start lower: the WHO's guidelines say some physical activity is better than none.⁸

Does the type of cardio matter?

Most of the research compares running and cycling, and it doesn't all agree:

• Long term, running may cost a little more. In the 2012 analysis, running alongside lifting reduced muscle growth and strength and cycling didn't.⁶ The 2022 fiber-level analysis found a negative effect on one fiber type with running but not cycling, though only three of its studies used running, and its authors call the evidence preliminary.⁷ They suggest a reason: running loads the muscles over and over as they lengthen on each landing, where cycling is mostly pushing.⁷
• For whole-muscle size and maximal strength, the type made no difference in the 2022 review of 43 studies.⁵
• Right before lifting, cycling hit leg strength harder. In the 2022 analysis of the minutes after a cardio bout, cycling caused a larger drop in leg strength than running.³ One more reason to do it after.

Walking is barely in these reviews. The cardio in the 2022 review's 43 studies was cycling or running, apart from one study each of a mix of the two, rowing and repeated leg extensions,⁵ and the 2021 review only counted cardio done above 70 percent of maximum heart rate.⁴ Easy walking isn't what these studies tested, so they say little about it either way.

If leg strength is your priority and you're choosing, the older and the fiber-level evidence lean toward cycling, done after lifting or on another day. Otherwise, pick the cardio you'll actually keep doing.

The short version

• Lift first when both are in one session and strength matters to you.
• New or returning: schedule it however your week works. Interference is a small concern next to showing up.
• Trained and chasing leg strength: more than two hours apart, or different days.
• Aim for both halves of the WHO guideline: two or more lifting days and 150 to 300 minutes of moderate cardio.
• Watch the trend. If your lifts stall as your cardio grows, trim the cardio before you change the lifting. (How often to train and which split cover the lifting side.)

If you'd rather have the week planned

Fitting lifting, cardio and the rest of your life into one week is a scheduling problem as much as a training one. Coaching is the version where your workouts live in the Trainerize app, built around the days you actually have, and a weekly call looks at the week you just had and rebuilds the next one around what's coming. How coaching works explains the rest, and applying takes about two minutes. Otherwise: put your lifting days in first, then the cardio around them.