How Much Strength Training Do Endurance Athletes Actually Need?

One of my triathletes thought plyometrics were a waste of his time. He'd trained consistently for three years, he was fit, and he couldn't see how a few jumps and bounds were going to do anything that more riding and running wouldn't. There was a fair bit of friction in those first few weeks. He did the work, but he wasn't sold.

Then around the ten-week mark, things started to show up. His heart rate was holding lower and steadier at paces that used to cost him more. His cadence had crept up. The paces themselves were starting to feel easier. The one that really landed for him came on race day: his run at the back end of a 70.3 felt noticeably stronger, and he wasn't as cooked coming off the bike as he had been before. He does plyometrics every block now. If I don't program them, he asks where they are.

I tell that story because it captures the whole point of this article. Strength work, including the springy stuff that feels pointless at first, doesn't make endurance athletes slower. Done right, it quietly makes everything else work better.

So how much do you actually need? For most endurance athletes, two strength sessions a week during normal training does the job. When racing season comes around you can drop to one or two. Each session takes 30 to 45 minutes and is built around a handful of heavy lifts. That is enough to make you more economical and more durable, and to keep you strong late in a race, without piling on the kind of bulk that slows you down.

This guide walks through why that works, what a session should look like, and how to fit lifting around your running, riding or swimming so the two don't get in each other's way. Everything here is based on published sports science, and the studies are listed in full at the end.

Who this is for: runners, triathletes, cyclists and age-group endurance athletes who want to get faster and more durable without strength work getting in the way of their training.

Quick answer. Most endurance athletes need about two strength sessions a week in normal training. Scale it by phase: 2 to 3 in base or off-season, 2 in normal training, 1 to 2 in race season and 0 to 1 in taper. Keep the lifts heavy and low in reps, train them after your key endurance work rather than before, then leave the day around your hardest sessions clear.

Strength training improves endurance performance mainly by improving economy, force production and fatigue resistance, not by raising VO₂max. That is the lever. It is why a small dose of heavy lifting makes you faster without the bulk most endurance athletes fear. If you want this built around your own race calendar, that is exactly what one on one coaching at Be is for.

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First, what are we actually trying to improve?

It is easy to assume endurance is all about your engine. Your VO₂max. How much oxygen your body can use when you're working flat out. The engine matters, but it isn't the whole story.

Picture two runners with the same VO₂max. One of them burns less oxygen holding race pace than the other. That runner has better economy, and over the course of a race that efficiency is what gets them to the line first. Economy is just how much energy it costs you to move at a given speed or power, and it happens to respond really well to strength training.

This is the idea the research keeps coming back to. Lifting doesn't make endurance athletes faster by growing the engine. It makes them faster by improving everything around the engine: how efficiently force gets produced and passed into the ground with every stride or pedal stroke.

Where the improvement comes from

A large 2024 review pooled 31 studies of distance runners and found that heavy strength training, plyometrics, and combinations of the two all improved running economy. Lighter, high-repetition work was much less convincing for this. A companion review looking at running performance found the same thing: the heavy and combined methods improved time-trial and time-to-exhaustion results, while barely touching VO₂max or sprint speed.

So the benefit is neuromuscular and mechanical rather than aerobic. Heavy lifting teaches your nervous system to recruit muscle more forcefully and more quickly. Plyometrics make your tendons stiffer and springier, so less energy leaks away each time your foot hits the ground. The engine stays the same size. You just get better at using it.

One detail worth knowing, because hardly any other training blog mentions it, is that the economy benefit depends on speed. The same review found that heavy lifting tends to help more at faster running speeds, while plyometric work tends to help more at slower ones. If you race fast, the barbell is doing most of the work for you. If you run long and steady, springy plyometric work earns its place.

"But won't lifting make me bulky and slow?"

This is the oldest fear in endurance sport, and the evidence just doesn't back it up. In one well-known study of trained distance runners, eight weeks of heavy strength training produced some striking changes while body weight and VO₂max both stayed exactly where they were:

A 5% improvement in economy might look small next to those headline strength numbers, but in endurance terms it's a big jump, the kind that actually shows up at the finish line. And it arrived without a single extra kilogram. Done properly, strength work improves the chassis rather than the engine. You get more force, better tissue tolerance, and cleaner mechanics deep into a race.

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How many sessions per week?

For most endurance athletes the useful range is one to three sessions a week, and where you land inside that range comes down to your training phase. The principle behind it is simple. You build strength when your endurance demands are lowest, then you hold onto it once racing ramps up. Strength is much easier to keep than to build, so you never have to give it up entirely.

Here is the same plan laid out in detail:

Training phase	Sessions/week	Session length	Main focus
Off-season / base	2–3	45–60 min	Build maximal strength with heavy compound lifts
Normal training	2	30–45 min	Progress or hold strength as endurance volume rises
Race season	1–2	20–40 min	Maintain, keeping the gains while shedding fatigue
Taper	0–1	20–30 min	Neural priming only, nothing that causes soreness

The maintenance phase rests on some solid evidence. In a study of well-trained cyclists, one group built strength over a 12-week preparation block and then dropped to just one strength session a week through the competition season. They kept the muscle and strength they had built, and it supported their cycling performance. The lesson is a freeing one. You don't have to choose between strength and racing. You earn the strength in the off-season and protect it with a minimal in-season dose.

I should be honest about one thing, though. The research doesn't prove that "two 30 to 45 minute sessions" is some magic universal number. That specific prescription is coaching judgement. It's the practical pattern that fits the evidence rather than a law handed down by a single study. Your own ideal dose will depend on your sport, your history, and how much endurance training you're already absorbing.

A quick opinion, while we're talking about priorities

Here's something I'll happily argue about. I think Zone 2 is overrated for most of the people chasing it. Not useless. Overrated. Zone 2 earns its reputation in athletes who can pour serious volume into their week, your pros and near-pros stacking up fifteen, twenty, twenty-five hours. At that volume, a big aerobic base built mostly from easy mileage makes complete sense.

But that is not who most of us coach. If you're an age-grouper training five to eight hours a week, your time is precious, and spending the bulk of it pottering along in Zone 2 is not where your biggest gains are hiding. For the time-poor athlete, Zone 2 is close to useless if it comes at the cost of actually hitting your key sessions, your threshold work, your race-pace efforts, and yes, your strength work. The aerobic base obsession has quietly crowded force development out of a lot of amateur programs, and I think that's backwards. When the hours are limited, intensity and strength buy you more than another easy hour ever will.

You don't have to agree with me. But before you fill your week with easy miles, ask whether you've actually got the volume to justify it.

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What a session should actually look like

A good strength session for an endurance athlete is short, heavy and simple. The classic mistake is turning it into another endurance session. Five sets of fifteen with short rests just heaps on fatigue and trains a quality you already have plenty of. You're in the gym for force.

Build each session in three layers.

The foundation is your main strength work. One or two big lower-body lifts will do it: a squat or leg press, a deadlift or hip hinge, plus a single-leg movement like a split squat or step-up. Aim for something like 3 to 5 sets of 3 to 6 reps, heavy but technically clean, with a full 2 to 3 minutes of rest between sets. Leave a rep or two in the tank, especially while you're learning. That long rest isn't laziness. It's what lets you lift heavy enough to actually get the neuromuscular benefit.

On top of that you can add a little power work, but only when you're fresh. A small dose of plyometrics like pogos, bounds or low jumps, done sharp and crisp. This is the part athletes push back on most, the same friction my triathlete gave me, and it's usually the part that surprises them later. They help economy, but they aren't free just because they only use your bodyweight. They load the tendons hard, so go easy on the volume.

Finally, add some resilience work aimed at your sport's usual trouble spots. Calves and Achilles, hamstrings, hips, trunk, matched to your own injury history. A runner with a cranky Achilles needs different accessory work than a cyclist with weak hip control.

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The interference effect, real but over-feared

If you've stayed out of the gym because you heard that lifting and endurance training cancel each other out, here's the honest version.

The interference effect is real. When you train strength and endurance at the same time, your maximal strength and power gains can come out slightly blunted compared with someone who only lifts. A 2024 review of 59 studies found this showed up as small interference for lower-body strength and a small-to-moderate effect for power. But it came with two big qualifiers. The effect was clearer in men than in women, and clearer in untrained people than in trained endurance athletes. Put simply, the fitter you already are, the less it seems to bite.

It also depends a lot on what kind of endurance work you do. An earlier meta-analysis found that running interferes with strength more than cycling does. That's probably because running's eccentric, muscle-damaging load overlaps more with whatever your legs are already trying to recover from in the gym.

Step back, though. As an endurance athlete you're not trying to win a powerlifting meet. You only need enough strength to lift your endurance performance. A small, manageable dent in your theoretical maximum strength is a price well worth paying, and you can mostly design it away with smart scheduling.

I had a runner who came to this the hard way. He did Olympic weightlifting as a hobby, so the lifting itself was never the problem, he was strong and he loved it. The problem was that he kept putting his weights sessions right before his threshold runs, and then couldn't work out why he was missing his paces session after session for a whole block. When we sat down the first question wasn't about his lifting at all. It was: what are we actually prioritising here? He was racing a half marathon, so the running had to come first. We didn't cut the weightlifting. We just periodised it around the key running so it stopped bleeding into the sessions that mattered, and there was a fair bit of trial and error shuffling things around his week before it clicked. Once it did, his paces came back.

That's the whole game with timing. It's rarely about doing less. It's about deciding what matters most on a given day and protecting it.

The three rules that make it work

Follow those three and the interference effect stops being something to worry about. It just becomes something you manage. If you'd rather not juggle the scheduling yourself, the Be app periodises strength and endurance together and adjusts as your week changes.

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Does strength training prevent injuries?

This is where a lot of fitness content gets carried away, so it's worth being careful with the wording.

Across sport in general, strength training has strong evidence behind it as a way to prevent injuries. A landmark 2018 review found it was one of the most effective exercise-based tools we have for cutting both acute and overuse injuries, and that bigger doses gave better protection.

In runners specifically, the picture gets messier. A 2024 review focused on endurance runners found that exercise-based prevention programmes did not clearly reduce running injury risk or rate overall, although how well a programme was supervised and stuck to seemed to matter. On the more encouraging side, a 2024 randomised trial found that a supervised hip-and-core programme cut lower-limb overuse injuries in novice runners. Tellingly, an ankle-and-foot programme in the very same study did not. So which exercises you choose, and how consistently you do them, clearly makes a difference.

The honest version of the claim is this. Strength training builds force capacity and tissue tolerance, and it can lower injury risk when it's targeted, progressive and done consistently. It is not a guarantee. For runners, how you manage your running load, meaning how fast you ramp up your mileage and intensity, still matters more than any gym programme. Strength is one important tool. It isn't a force field.

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Common mistakes

• Too much volume. You already carry a heavy load from your endurance training. More gym sets isn't automatically better, and it often makes things worse.
• Training to failure. It heaps on soreness and recovery cost for very little extra benefit toward what you're actually chasing.
• High-rep "toning" circuits. They build local muscular endurance you already have in spades. They don't build the maximal force that improves economy.
• Quitting strength entirely in-season. The most common error of the lot. A single weekly maintenance session keeps the gains you worked for, while dropping to zero throws them away by spring.
• Bad timing. Heavy legs the day before a key endurance session isn't toughness. It's just poor programming.

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Key takeaways

• Two strength sessions a week suits most endurance athletes in normal training, and one to two is plenty once you're racing.
• Lift heavy and keep the reps low. You're training force and efficiency, not chasing muscle size.
• Strength work lifts performance mainly by improving economy and fatigue resistance, and it can do this without adding body weight.
• Build your strength in the off-season and maintain it in-season. One weekly session is enough to hold what you've got.
• Manage the interference effect with session spacing and a clear daily priority rather than fearing it.
• Be careful with injury-prevention claims. Strength helps your capacity, but running injuries are driven mostly by load and how you progress it.

Used well, strength training doesn't compete with your endurance training. It quietly makes all of it work better.

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Putting it to work

If you want strength built around your own training and your goal race rather than a generic template, that is what I do. I'm Brendon Villanueva, an ESSA-accredited Sport Scientist at Be Sports Science Consulting. I provide sports science coaching for runners, triathletes and hybrid athletes, one on one and online. Book a consultation and we'll map strength programming around your race calendar.

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References

1. Llanos-Lagos C, Ramirez-Campillo R, Moran J, Sáez de Villarreal E. Effect of Strength Training Programs in Middle- and Long-Distance Runners' Economy at Different Running Speeds: A Systematic Review with Meta-analysis. Sports Medicine. 2024;54(4):895–932. https://doi.org/10.1007/s40279-023-01978-y

2. Llanos-Lagos C, Ramirez-Campillo R, Moran J, Sáez de Villarreal E. The Effect of Strength Training Methods on Middle-Distance and Long-Distance Runners' Athletic Performance: A Systematic Review with Meta-analysis. Sports Medicine. 2024;54(7):1801–1833. https://doi.org/10.1007/s40279-024-02018-z

3. Støren Ø, Helgerud J, Støa EM, Hoff J. Maximal Strength Training Improves Running Economy in Distance Runners. Medicine & Science in Sports & Exercise. 2008;40(6):1087–1092. https://doi.org/10.1249/MSS.0b013e318168da2f

4. Paavolainen L, Häkkinen K, Hämäläinen I, Nummela A, Rusko H. Explosive-strength training improves 5-km running time by improving running economy and muscle power. Journal of Applied Physiology. 1999;86(5):1527–1533. https://doi.org/10.1152/jappl.1999.86.5.1527

5. Huiberts RO, Wüst RCI, van der Zwaard S. Concurrent Strength and Endurance Training: A Systematic Review and Meta-Analysis on the Impact of Sex and Training Status. Sports Medicine. 2024;54(2):485–503. https://doi.org/10.1007/s40279-023-01943-9

6. Wilson JM, Marín PJ, Rhea MR, Wilson SMC, Loenneke JP, Anderson JC. Concurrent Training: A Meta-Analysis Examining Interference of Aerobic and Resistance Exercises. Journal of Strength and Conditioning Research. 2012;26(8):2293–2307. https://doi.org/10.1519/JSC.0b013e31823a3e2d

7. Lauersen JB, Andersen TE, Andersen LB. Strength training as superior, dose-dependent and safe prevention of acute and overuse sports injuries: a systematic review, qualitative analysis and meta-analysis. British Journal of Sports Medicine. 2018;52(24):1557–1563. https://doi.org/10.1136/bjsports-2018-099078

8. Wu H, Brooke-Wavell K, Fong DTP, Paquette MR, Blagrove RC. Do Exercise-Based Prevention Programs Reduce Injury in Endurance Runners? A Systematic Review and Meta-Analysis. Sports Medicine. 2024;54(5):1249–1267. https://doi.org/10.1007/s40279-024-01993-7

9. Leppänen M, Viiala J, Kaikkonen P, Tokola K, Vasankari T, Nigg BM, Krosshaug T, Werthner P, Parkkari J, Pasanen K. Hip and core exercise programme prevents running-related overuse injuries in adult novice recreational runners: a three-arm randomised controlled trial (Run RCT). British Journal of Sports Medicine. 2024;58(13):722–732. https://doi.org/10.1136/bjsports-2023-107926

10. Rønnestad BR, Hansen EA, Raastad T. In-season strength maintenance training increases well-trained cyclists' performance. European Journal of Applied Physiology. 2010;110(6):1269–1282. https://doi.org/10.1007/s00421-010-1622-4

11. Rønnestad BR, Mujika I. Optimizing strength training for running and cycling endurance performance: A review. Scandinavian Journal of Medicine & Science in Sports. 2014;24(4):603–612. https://doi.org/10.1111/sms.12104

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Written by Brendon Villanueva, ESSA-accredited Sport Scientist at Be Sports Science Consulting (BExSpSc). This article is general information rather than individual medical or training advice. Check with a qualified professional before making big changes to your training.