Cardio before or after weights? How to combine cardio and strength training

For health, the order hardly matters

The NHS says you can do muscle-strengthening activities on the same or different days as your aerobic activity, whatever's best for you. Doing both matters more than the order.

Source 1

Cardio doesn't cost you muscle or maximal strength

Across 43 studies, adding aerobic training to strength training didn't reduce muscle growth or maximal strength. It did blunt explosive strength, such as jump height, a little.

Source 2

If strength matters most, lift first or separate them

Lifting first built slightly more leg strength in pooled trials, about 7% or 4 kg more, with the same gains in fitness and fat loss. The trials were small, and one with 3 hours between sessions found no difference by order.

Sources 3, 4, 5, 6

If endurance matters most, run or ride first

A hard lifting session can leave your legs heavy for hours to days. Runners: lift more than 3 hours after a hard run, and leave at least a day before the next hard run.

Sources 7, 8

Spacing matters for strength and power

Explosive gains were blunted mainly when both were done in the same session, and trained lifters lost some leg strength only in same-session designs. In rugby players, a day between sessions gave the biggest gains.

Sources 2, 9, 10

For fat loss, order doesn't matter

Body fat didn't differ by order in pooled trials, and studies of the afterburn disagree on which order burns more. Your total activity and what you eat matter far more.

Sources 3, 11, 12

Concurrent training

Doing aerobic (endurance) training and strength training in the same programme, whether in one session, on the same day or on different days.

Sources 2, 13

Where the interference idea came fromEmerging evidence

In a 1980 study, people did strength training 5 days a week plus 40 minutes of endurance training 6 days a week. Their strength rose as fast as a strength-only group's for 7 weeks, then levelled off and fell in weeks 9 and 10, while their aerobic fitness rose as much as an endurance-only group's. That was a very large amount of training.

Source 14

Why hard cardio and lifting tire each otherEmerging evidence

In 16 men, leg-press reps fell 4 and 8 hours after hard or steady cycling, but not after 24 hours, and only in the muscles the cycling had used. The other way round, a hard lifting session can impair endurance sessions for several hours to days, through changes in how muscles are recruited, less efficient movement, soreness and lower fuel stores.

Sources 15, 8

What happens inside the muscleMixed evidence

Endurance exercise was once thought to switch off the signals that build muscle. Studies in people haven't consistently shown this, and several processes are probably involved together, so the mechanism isn't fully understood.

Sources 16, 17

Muscle and maximal strengthStrong evidence

A 2022 meta-analysis of 43 studies (1,090 people) found that adding aerobic training to strength training didn't reduce muscle growth or maximal strength, whether the cardio was running or cycling, and whatever people's age or training status. Study quality was middling on average.

Cardio may even help muscle in some cases: in 10 men, 45 minutes of one-leg cycling 6 hours before knee extensions grew the quadriceps more over 5 weeks (14% against 8%). In middle-aged and older adults, combined training built as much muscle as strength training alone and cut as much fat as aerobic training alone (53 studies).

Sources 2, 18, 19

Explosive strengthEmerging evidence

Explosive strength, measured as jump height, how fast force builds and leg-press power, rose a little less with combined training (a small effect, 18 studies). Sprinting wasn't measured.

Source 2

Who sees some interferenceEmerging evidence

In trained people, adding endurance training cut leg-press and squat gains a little, but only when both were in the same session (under 20 minutes apart), not in separate sessions more than 2 hours apart. Untrained and moderately trained people showed no clear effect (27 studies, 750 people).

In 59 studies of adults aged 18 to 50, men showed a small blunting of leg strength gains and women didn't, though there were fewer data in women. An older analysis found interference grew with how often and how long people did endurance training.

Sources 9, 20, 21

Lifting first: a small edge for leg strengthEmerging evidence

Three meta-analyses of same-session training agree that lifting first gives slightly more lower-body strength: about 7% more (10 studies, 245 people), about 4 kg more on the most you can lift once, and a small advantage in a third analysis of 19 trials, clearer in older adults, women and programmes longer than 8 weeks. None found that order changed muscle growth or aerobic fitness, and the one that measured body fat found no difference.

The trials were small, and in 29 men who did intervals 3 hours before or after lifting for 9 weeks, strength, lean mass and fitness improved the same either way. The 2026 overview of reviews by the American College of Sports Medicine (ACSM) found too little evidence on same-session training to judge.

Sources 3, 4, 5, 6, 13

The 3-hour gapMixed evidence

In the 43-study analysis, explosive strength was blunted when both were done in the same session but not clearly when they were at least 3 hours apart. That came from comparing groups of studies, not from a trial that tested the gap, and one trial still found blunted jump power with 3 hours between when intervals came after lifting.

In 58 amateur rugby players who always lifted first, a full day between strength and aerobic sessions gave the biggest strength gains and no gap the smallest; the authors advise leaving at least 6 hours. Our plans keep hard cardio at least 3 hours from heavy leg work, or on another day.

Sources 2, 9, 6, 10

HIIT and liftingEmerging evidence

Adding HIIT to strength training didn't reduce muscle growth or upper-body strength in pooled trials; leg strength gains were slightly smaller.

Source 22

Running or cycling: which interferes more?Mixed evidence

A 2012 analysis of 21 studies found running, not cycling, reduced gains in muscle and strength; a 2018 analysis of HIIT leaned the other way, with a non-significant trend against cycling; the largest, in 2022, found no difference. Choose the cardio you enjoy.

Sources 21, 22, 2

Older adultsEmerging evidence

In 26 men aged about 65 who trained 3 times a week for 12 weeks, strength before endurance raised leg strength 35% against 22%, with the same gains in muscle thickness and aerobic fitness. Pooled trials also found the lift-first edge clearer in older adults.

Sources 23, 24, 5

General health and fitness

Either order, on the same day or different days. If one part tends to get skipped, do it first (our suggestion).

Source 1

Strength or muscle

Lift first, or do the cardio in a separate session. Keep the cardio steady if it comes straight after heavy leg work.

Sources 3, 4, 5, 9

Running, cycling or another endurance goal

Do the key run or ride first, or on another day. Lift more than 3 hours after a hard run, and leave at least a day before the next hard run or long run, as our running plans do.

Sources 7, 8

Leg strength or power: sprinting, jumping, strength sports

Keep hard cardio and heavy leg sessions at least 3 hours apart, ideally on different days, and put hard intervals on upper-body or rest days (our plans' rule).

Sources 2, 9, 10

Fat loss

Either order: pick the one that means you do both, and look at your weekly activity and food. Our weight-loss guide has the detail.

Sources 3, 25

Older adults

Strength first is a sensible default.

Sources 24, 5

Type 1 diabetes

In one small trial, weights before a run kept blood glucose steadier during exercise, and lows afterwards tended to be shorter. Agree a plan with your diabetes team; our weights then cardio workout builds in the glucose checks.

Source 26

How far apart

Our rule, from the trials: if leg strength or power is your priority, at least 3 hours between hard cardio and heavy leg training, or separate days. For runners, more than 3 hours after a hard run before lifting, and a day before the next one. Everyone else can do both in one session.

Sources 2, 7, 10

Easy cardio before lifting is fine

A few minutes of easy cardio is a good warm-up: 20 easy minutes on a bike before a leg-press test raised the maximum by 8.4% in 13 trained people. It's long or hard cardio that tires your legs for hours.

Sources 27, 15

Cardio on leg day

An easy walk or ride after leg training is fine. Hard cycling or intervals before heavy leg work cut the reps people could manage for up to 8 hours, so put them on another day if leg strength matters to you.

Sources 15, 2

Order doesn't change fat lossEmerging evidence

Body fat didn't differ by exercise order in pooled same-session trials. The afterburn, the extra energy used after a session, was greatest with running first in one study of 10 men and didn't differ in another of 7. In type 2 diabetes, 27 trials (965 people) found both orders improved body fat, blood sugar and cholesterol, and neither was shown to be better.

Sources 3, 11, 12, 25

What does matter

Your total activity across the week and what you eat. Do the order you'll stick to.

Three strength days

Strength on Monday, Wednesday and Friday; easy cardio or a walk on Tuesday and Saturday (our 3-day plan).

Four strength days

Upper and lower days on Monday, Tuesday, Thursday and Friday; cardio on Wednesday or Saturday, with hard intervals kept away from the lower days (our 4-day split).

Runners who lift

Lift after an easy run, or later on the day of a hard run, ideally 3 or more hours after, and never the day before intervals or a long run (our strength training plan for runners).

Hyrox

Lift at least 3 hours after Tuesday's hard run and keep a day between lifting and the next hard run; if you must combine them, lift first (our Hyrox plan).

Everything in one visit

Strength first, then 20 to 30 minutes of steady cardio, as in our weights then cardio workout.

Feeling faint after hard cardio

Stopping dead after a hard effort can make you light-headed. Keep walking slowly, or lie down with your legs raised, and drink some water. See a GP after any faint.

Sources 28, 29

Type 1 diabetes

Exercise order changes blood glucose during and after a session, so follow your diabetes team's plan and check your glucose. Our type 1 diabetes guide has more.

Source 26

Call 999 now (911 in the US)

Stop and call 999 (don't drive yourself to A&E) for:

• Chest pain that feels tight, like squeezing or pressure, or like burning or indigestion and doesn't go away, or pain that spreads to your arms, neck, jaw, stomach or back.
• Chest pain with sweating, feeling sick, light-headedness or breathlessness.
• Severe difficulty breathing: gasping, choking or not able to get words out.
• Someone who faints while exercising, can't be woken within a minute, or hasn't fully recovered.
• A headache that starts suddenly and is extremely painful, or comes with numbness or weakness, trouble speaking, confusion or loss of vision.

Sources 30, 31, 29, 32

Get help the same day: NHS 111 (in the US, your doctor or urgent care)

• You're suddenly more short of breath than usual, or have chest pain with a heartbeat that races, slows, skips or flutters.
• A headache that exercise brings on or makes worse: ask for an urgent GP appointment or contact 111.
• An injury that is very painful or getting worse, swells a lot, or that you can't put weight on. Call 999 or go to A&E if you heard a crack or the injured part has changed shape.
• In the days after an unusually hard session: dark, red or cola-coloured urine, passing less urine, or muscle pain, stiffness or weakness far worse than normal soreness. These can be signs of rhabdomyolysis, a breakdown of muscle that can harm the kidneys.

Sources 30, 32, 33, 34

See a GP

• After any faint, even if you feel fine now.
• Before you start, if you haven't exercised for some time or have a medical condition or concerns.
• If new symptoms appear as you do more. Light or moderate activity doesn't usually need a check first if you have no health conditions.

Sources 29, 1, 35

Stop and swap

Stop straight away if you feel pain or become unwell, and contact NHS 111 if a symptom worries you or doesn't go away. A joint pain that is sharp, gets worse during a set, lingers into the next day or changes how you move is a reason to use the move's easier option, and to see a GP or physiotherapist if it keeps happening (the rule in our plans). Muscle soreness for a day or two after something new is normal.

Source 36

"Cardio kills your gains"Strong evidence

Not muscle or maximal strength, across 43 studies. It can blunt explosive strength a little, mainly when both are in the same session.

Source 2

"Do cardio after weights to burn more fat"Emerging evidence

Order didn't change body fat in pooled trials. The afterburn was larger with running first in one study and no different in another, and it's a small amount of energy either way.

Sources 3, 11, 12

"Lift first to keep your hormones high"Emerging evidence

The brief rise in hormones after lifting didn't add muscle or strength in trials. Lift first because your legs are fresh, not for hormones.

Sources 37, 38

"Never do cardio on leg day"Emerging evidence

Easy cardio is fine. It's hard cardio within a few hours of heavy leg work that can cost leg strength or power.

Sources 15, 2, 9

"Whichever you do second, you're more likely to get injured"

Popular articles say this of lifting after cardio, or of cardio on tired muscles, but cite no study, and we found none. Do keep your form, and stop a set when it slips.

"Running interferes more than cycling", or the reverseMixed evidence

The analyses disagree, and the largest found no difference. Choose the cardio you enjoy.

Sources 21, 22, 2