How to Improve Cycling Endurance: What the Research Says

Advice on improving cycling endurance often contradicts itself: ride easy, ride more, ride in zone 2, add intervals. Most articles on the topic don't cite a single study.

Here is what meta-analyses and expert opinions say, followed by how to turn that into a week that fits your schedule.

The "80/20" split: an observation in elites, not a rule for everyone

In 2010, researcher Stephen Seiler described what national and international-level endurance athletes do. They train 10 to 13 times a week. About 80% of their sessions are low intensity, and about 20% include hard work.

This model is called polarized training. Comparison studies are more nuanced:

• A 2024 meta-analysis (17 studies, 437 adults) finds a small advantage for polarized training on VO2peak, mostly in short interventions and in highly trained athletes. For time trials, there is no difference.
• A 2025 meta-analysis of trained cyclists concludes that polarized and non-polarized training bring comparable gains in VO2max and time trial performance.
• A 2019 meta-analysis, based on only 3 studies, suggested a time trial advantage for polarized training. The 2024 authors explain the gap by the number of studies included.

So don't look for the perfect percentage formula. Remember that a large share of your training should be easy, and that intensity gets added in small amounts.

Zone 2: a useful guide, not a switch

In 2025, 14 experts (scientists and professional cycling coaches) agreed on a definition: zone 2 is the intensity just below the first lactate or ventilatory threshold. You can hold it steady, vary it, or use it in intervals.

They don't expect large differences in adaptation between zone 2, the top of zone 1, and the bottom of zone 3. The body's responses form a continuum: one watt more or less doesn't change your ride into a different category.

This consensus is an expert opinion, not a controlled trial, and some researchers dispute that zone 2 is the best intensity for everyone. Coaches suggest riding at a pace where you can speak in full sentences, without worrying about a few beats per minute.

Volume or intensity: what to do when you're short on time

The 2025 meta-analysis of trained cyclists offers a useful conclusion: beyond a necessary volume, adding more volume doesn't seem to improve performance. Riding more and more is not the only way forward.

On intensity, Seiler reports that in well-trained athletes who only did base endurance work, adding two interval sessions a week for 4 to 8 weeks improved performance by 2% to 4%.

The same text notes that in athletes who are already well trained, there is no proof that pushing intervals further brings long-term gains. Intensity is there to unlock progress, not to fill your week.

When time is short:

• A shorter ride with a block of intensity is worth more than a short, easy-going ride.
• A longer, easy ride still helps your endurance.
• Three steady rides are worth more than five rides where two get skipped.

Strength training: useful for pedaling economy

A 2014 review of runners and cyclists recommends heavy strength training, alongside endurance work, to improve pedaling economy: producing the same power while using less energy.

Effects on power or speed at lactate threshold vary from study to study. So don't count on the gym to add watts at threshold. If you're new to it, have someone show you the movements. If pain persists, talk to a doctor.

Eating and drinking based on ride length

The German-speaking sports medicine position (König et al., 2020) gives these guidelines:

The 2016 joint US-Canadian position statement says no carb intake is needed for efforts shorter than 45 minutes. Under that length, water is enough.

Don't aim for 90 g per hour over two hours: that figure is for very long efforts, and your stomach needs time to adapt. To check whether your plan worked, read our article on fueling for long rides.

What you can do on your next ride

1. Pick your weekly schedule and stick to it for 4 weeks: for example, two easy rides and one with intervals.
2. Ride truly easy. If you can't hold a conversation, slow down.
3. Add a block of intensity only if your easy rides are going well, and keep it short.
4. Schedule heavy strength sessions on the same days each week.
5. Plan your fueling before any ride longer than an hour.
6. Compare on the same route: same loop, same pace or power, and check whether your heart rate is lower than it was a month ago.

ELYO reads your watch's workout data, analyzes pace, heart rate, volume, and consistency, then adjusts your plan. It helps with the last step: spotting over several weeks whether your heart rate drops at the same effort.

Written with the help of AI.