How many days a week should endurance athletes strength train?

If you run, cycle, or swim, strength training will come up sooner or later. You might think, “I already train enough. Do I really need strength sessions too?” The aim here is to build a stronger, more efficient body that can better withstand the demands of running, pedaling, or swimming. You don’t need to take on a bodybuilding program to do that. Looking at it this way makes the value of strength training a little easier to see.

Let’s start with the short answer: for most recreational endurance athletes, two strength sessions a week are a useful, sustainable starting point. If you’re new to it, beginning with one session a week for the first few weeks makes perfect sense too. A third session should only enter the picture if you’re recovering well, your training volume allows it, and you actually need it.

What does strength training offer endurance athletes?

It’s easy to think of endurance sport as being all about your heart and lungs. But if your form falls apart towards the end of a long run, you struggle to keep your hips stable on climbs, or your shoulders tire early when swimming, you soon discover—sometimes the hard way—that strength and muscular endurance matter too.

Well-planned strength training can help you:

• Move with better control at the same pace
• Stay stronger on climbs, during sprints, or through technical sections
• Maintain your form better towards the end of a long session
• Support your hips, calves, hamstrings, core, and the muscles around your shoulders
• Address some of the imbalances that can develop when your training consists of “just running more”

Let’s be clear about one thing, though: strength training isn’t a magic wand. If you aren’t giving sleep, nutrition, and your main sport the attention they need, strength work alone won’t make up for that. In the right place in your program, however, it can be valuable support, especially over the long term.

New to it? You can start with one day a week

If you’ve only recently started running or cycling regularly, you don’t need to fill your schedule with heavy strength days straight away. Unfortunately, some of us get carried away at the start and soon reach the “Everything hurts. I’m giving up” stage. What matters is finding something you can keep doing.

For the first 3–4 weeks, you can begin with one full-body session a week. Give your body time to get used to the movements, particularly to loading them with control. Some mild muscle soreness the next day is normal. But if you’re so sore that it changes your running form, that’s a sign you’ve done too much.

Once that routine feels settled, you can move up to two days a week. For most people, that’s the sweet spot.

For most recreational athletes, two days makes the most sense

After establishing a weekly session, moving to two strength days leaves time for your main sport while letting you develop the movements consistently. For example, adding two short strength sessions to three weekly runs doesn’t mean turning all five days into hard training days.

Those sessions don’t have to last 45–60 minutes either. At the start, two well-planned sessions of 25–40 minutes can go a long way. Focus on movement quality rather than training to failure every time. Finishing with the feeling that you could have done a little more isn’t a bad thing, especially for an endurance athlete.

When does a third strength day make sense?

A third day only makes sense once you’re completing two sessions consistently and recovering comfortably. There’s little value in forcing an extra day when your body isn’t recovering, simply for the sake of doing more. What you get out of the training matters more. That third session doesn’t have to be another heavy leg day, either. It could be a short support session for your core, hip stability, ankles and calves, upper body, or an area you feel needs more work.

Especially when preparing for a race, ask yourself: “Is this session making me stronger, or is it compromising tomorrow’s quality run?” If the second answer seems more likely, plan your two sessions better before adding a third.

Where should strength training fit into your week?

Placement matters more than the number of days. For most people, heavy leg training immediately before a fast run, intervals, hills, or a long run doesn’t work particularly well. Two approaches are often useful:

On the same day, in the right order

If you have a quality running or cycling session planned, you can put strength work later that day. Do your main sport first, then strength a few hours afterwards. If that isn’t possible, follow it immediately with a more controlled strength session. That way, the next day can genuinely stay easy.

A short session after an easy workout

Another practical option is 20–30 minutes of strength work after an easy run. Be careful not to overdo the load. An “easy day” should still feel easy.

Which exercises should endurance athletes focus on?

Your program will depend on your sport and any past injuries. For most runners and cyclists, though, the hips, single-leg control, calves, hamstrings, and core are good places to focus. Swimmers can add the back, shoulder blade control, and the muscles around the shoulders to that list.

An example full-body session might include:

• Goblet squat or leg press
• Hip thrust or glute bridge
• Step-up or controlled split squat
• Calf raise
• Push-up, chest press, or shoulder press
• Cable or resistance band row
• Plank, dead bug, or Pallof press

You don’t have to do every exercise. Five or six well-chosen movements, with 2–3 sets and controlled repetitions, are enough to get started. Don’t rush to add weight to a new exercise. Good form matters more than an impressive-looking load.

“Will training my legs make my running worse?”

It’s normal for your legs to feel heavy after the first few sessions. But don’t immediately conclude that strength training has ruined your running. It’s usually part of adapting to a new load. Problems arise when the strength work is too heavy, involves too much volume, or lands on the wrong day.

Trying heavy squats for the first time during race week, or doing an intense leg session the day before a long run, clearly isn’t a great idea. But regular, measured strength training throughout the season doesn’t have to clash with your running.

Should I stop strength training during race season?

Rather than dropping it completely, you can reduce the volume. In the weeks before a race, the aim is to maintain strength, rather than create fresh muscle soreness. I doubt many of us are hoping for extra soreness anyway. You can shorten the sessions, reduce the number of sets, or avoid adding new exercises.

It’s a good idea to reduce heavy leg loading in the final 5–7 days before your main target race—often called your “A race.” There’s no single formula for everyone here. Watching how you recover gives you the most useful information.

A quick overview

A final thought

For an endurance athlete, the value of strength training lies less in how many days you do it and more in how consistently you keep it up. An imperfect but regular two-day plan is far more useful than a three-day program you abandon after two weeks.

First, build a routine that doesn’t get in the way of your main sport. Then think of strength work as a supporting player for your race goals. Being strong isn’t only about lifting heavier weights. It’s also about keeping your form at the end of a session and being able to get moving again the next day. If you want to adjust strength work to your effort level, have a look at our guide to RPE. To learn how to build your endurance foundation, try our guide to base training, or explore the other guides in our Training category.