Lifting heavy probably won’t slow you down. In a 2025 meta-analysis of 262 cyclists, heavy lifting made riders more efficient and more powerful, and VO2max didn’t move in any way the researchers could detect.
That surprises people. Many riders assume bigger legs mean extra weight to haul uphill. The data says the gain shows up somewhere else.
What the 2025 meta-analysis found
Researchers pooled 17 controlled studies with 262 cyclists. Each study added heavy strength training (80% of one-rep max or more, for at least 3 weeks) and compared it with riding alone. A one-rep max is the heaviest weight you can lift once.
Results are reported as Hedges g, a standard score for effect size. Around 0.2 is small. Around 0.5 is moderate. Zero means no change.
Translation: the bigger the number, the bigger the gap between lifters and non-lifters.
Three outcomes improved. Efficiency, anaerobic power and performance all passed the significance bar. VO2max, power at VO2max and anaerobic capacity did not.
In short: lifters got better at turning effort into speed. Their ceiling for oxygen use stayed put.
Why VO2max stays flat while efficiency and power improve
Picture a car with a fixed fuel tank. Strength work doesn’t build a bigger tank. It tunes the engine so each liter takes you farther. Your VO2max (the most oxygen your body can use per minute) is the tank. Cycling efficiency is the miles per liter.
The researchers offer a few ideas for why this might happen. Stronger legs push on the pedals with a smaller share of their maximum force per stroke. That may let slower, more economical muscle fibers do more of the work. One study also linked bigger quadriceps to better efficiency (r = 0.535).
Here is the catch. None of those mechanisms were measured in the efficiency studies. They are educated guesses. “The gain comes via efficiency” is the best reading of the pattern, not a proven finding.
Anaerobic power improved too. So efficiency isn’t the whole story.
Two studies also found the efficiency boost after long, tiring rides. That fits what many riders feel: fresh legs in the final hour.
Why the evidence is only low certainty
Every analysis was rated low certainty on the GRADE scale, a system for grading how far you can trust a result. The reasons are plain. Studies were small. Riders weren’t randomly assigned to groups in most trials. The average quality score was 5.53 out of 7.
The VO2max result needs care. “No significant change” means no change was detected. The confidence range ran from -0.345 to 0.263, which is wide. A small gain or a small loss can’t be ruled out.
Other limits matter for you:
- Riders mostly had no earlier lifting history.
- The longest trial lasted 25 weeks.
- Few women were studied.
- Most trials added lifting on top of normal riding, so total training load went up.
Some coaching blogs say the review “settled” the question. It didn’t.
Strong lead. Not a verdict.
Heavy lifting vs plyometrics
Plyometrics are jumps and bounds. Several studies in the review mixed them into the heavy-lifting groups. So the paper can’t tell you which method wins.
An earlier review by Rønnestad and Mujika (2014) favored heavy loading for cycling economy. That is a separate source with its own limits. Use it as a nudge toward heavy sets, not as a head-to-head result.
A practical heavy strength training block
The meta-analysis found no clear effect from session count or program length. So there is no magic dose. A reasonable starting plan follows the studies’ definition:
| Setting | Starting point |
|---|---|
| Load | 80% of one-rep max or more |
| Reps | 3-5 per set, 3-4 sets |
| Lifts | Squat or leg press, plus a hip hinge |
| Frequency | 2 sessions per week |
| Length | 6 weeks, then reassess |
| Timing | Not before your hardest ride |
Keep your normal riding easy enough to absorb the extra load. You’re adding stress, not swapping it. Our guide on how to combine strength and endurance training covers how to keep easy days easy.
Phase matters too. Put the block in your base period, then taper the lifting as race season nears. Sequential periodization shows how to shift intensity through the year. To see where your threshold sits before you start, read what FTP means for cyclists.
How to progress the load
The studies don’t prescribe a progression, so this part is coaching practice, not trial data. It’s a sensible way to apply the 80% rule.
Start with the first two weeks light. Use a weight you could lift for 8 reps, but stop at 5. Learn the movement first. Sore legs on Monday won’t help your Tuesday ride.
From week 3, move to sets of 4 reps near 85% of your one-rep max. When you hit every rep of every set with clean form, add 2 to 5 percent next session. If a set breaks down, hold the weight.
Stop each set with a rep or two left. Grinding to failure adds fatigue without adding much. You want strong legs, not wrecked ones.
Translation: lift heavy, lift fresh, and add weight slowly.
What to do in race week
Don’t test a new lift in race week. Don’t try a new max. Soreness is the last thing you want on the start line.
In the final 7 to 10 days, cut volume and keep the weight. One short session of 2 sets of 3 reps at your usual load is plenty, and it should be done early in the week. Then skip the gym until after the race.
If you’re on a taper plan, treat lifting as part of it. Less volume, same load, more rest.
How to check it’s working
The meta-analysis has no data on individual riders. Your legs might respond more or less than the average. So test yourself.
Pick a steady power, say 200 watts. Ride 20 minutes at that power on the same route or trainer each week. Write down your average heart rate. If the block works, the same watts should cost fewer beats.
Take a rider I’ll call Dan: 44, riding 8 hours a week, never lifted seriously. In week 0, his heart rate at 200 watts averaged 152. He added two heavy leg sessions a week. By week 6 it was 147, and his 20-minute test power hadn’t changed. (This is a made-up example.)
Same power. Five fewer beats. That is the pattern the meta-analysis predicts.
Flat VO2max and rising efficiency is what you hope to see. AthleteOS tags your strength sessions on the workout calendar, then uses workout import and session analysis to track heart rate at fixed power across the block. It also tracks your drift ratio late in long rides, a proxy for how well you hold up when tired. It’s a personal proxy, not a lab measure.
Who should expect gains
Newer lifters have the most to gain. The riders in these trials had no prior systematic strength training, or their experience wasn’t reported. If you’ve lifted for years, your response may be smaller.
Masters riders and women are under-studied here. That doesn’t mean it won’t work. It means the proof is thinner.
Here is a second gap. The longest trial lasted 25 weeks, so nobody knows what happens over several seasons. And the pooled results are averages. The meta-analysis has no individual-response data. Some riders in those studies likely gained a lot and some gained nothing. You can’t tell which group you’re in from the average.
That’s why a personal check matters. Run the fixed-power test above and let your own numbers decide.
Why late-ride efficiency matters for Ironman riders
Two studies in the review found better efficiency after prolonged submaximal cycling. Efficiency may show up mainly when you’re tired. That’s early evidence, and the mechanism wasn’t tested.
Still, think about what it could mean for a long-course rider. An Ironman bike leg is 112 miles. Your legs at mile 100 don’t pedal like your legs at mile 10. If lifting keeps each stroke cheaper late in the ride, you arrive at the run with more in the tank.
A fresh-legs test could miss that. Check your drift ratio on long rides too. If heart rate climbs less in the final hour at the same power, your base is holding up. Pair that with the fixed-power test for a fuller picture.
Read the Rønnestad and Mujika review and the 2025 meta-analysis if you want the full detail. When you’re ready to track your own block, start your free trial of AthleteOS.