Guide
How do you combine running and lifting in one week?
Do both, because lifting does not reduce your endurance and it makes runners more economical. What costs you is timing, so keep heavy legs and hard runs apart.
Last updated: 2026-10-13
By Ole Fiegenbaum, founder of Loadcast. Before the app, Ole's triathlon training ran through one ChatGPT chat. More on the landing page.
How this page was made: the rules and example weeks come from the Loadcast engine, and every example week runs through the same check as the app. The studies are linked. The text was written with AI help.
Lifting does not hurt your running
Lifting makes runners more economical and does not reduce VO2 max or blood lactate. This is why you keep lifting through a race block instead of dropping it.
Blagrove et al. 2018. Sports Med. Strength training and middle and long-distance running performance, systematic review. DOI 10.1007/s40279-017-0835-7
Berryman et al. 2018. Int J Sports Physiol Perform. Strength training for middle and long-distance performance.
Arms and back do not slow your legs
Interference is body-part specific, not systemic. Training your arms and back does not slow your legs.
Wilson et al. 2012. J Strength Cond Res. Concurrent training meta-analysis. PMID 22002517
Coffey & Hawley 2017. J Physiol. The molecular basis of concurrent training. PMC5407958
What to do
- Put upper-body lifting on or next to your hard run days.
- Keep heavy leg work away from the day before a hard run.
- Space your hard sessions by six to 24 hours, so both adaptations are protected.
- If two or more of your endurance sessions this week came without a lift, lift next.
An example week
This week passes the next-day rules the app runs (legs before a hard run, long run before legs, two hard days in a row), with no day moved.
Monday: upper body, 60 minutes.
Tuesday: intervals, 50 minutes.
Wednesday: easy ride, 60 minutes.
Thursday: heavy legs, 60 minutes.
Friday: easy run, 45 minutes.
Saturday: long run, 100 minutes.
Sunday: rest.
- If your long run is Sunday, put heavy legs on Wednesday or Thursday, not on Monday.
- If your tempo run is Friday and your long run Saturday, the long run turns into an easy run. Move the tempo run to Thursday or earlier.
What Loadcast does with this
In the app, the matching rule reads like this.
Upper body is sore. Shifting to lower body or easy run. Upper-body micro-damage doesn't limit lower-body or aerobic capacity. Training continues without conflict. Legs or easy aerobic today. Upper body recovers in the background.
Two or more endurance days without a lift. Strength balances the week. Concurrent training needs a weekly strength stimulus to protect power and tissue resilience. One lift puts the week back in balance.
Every rule with its mechanism is on How Loadcast decides, the studies are on The research behind our content.
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