One of the most popular questions asked by people beginning a fitness campaign is which is best – cycling or running?

There’s no simple answer, of course, as each sport has its own pros and cons.

Running requires little equipment other than decent running shoes and is arguably a much more agreeable pastime than cycling when the weather is foul. It’s also very efficient in terms of fitness gains per hour invested. However, cycling is still a great fitness builder and the smooth pedalling action is much easier on the joints, which means a much lower risk of injury.

Cycling is also a great way to get from A to B, making it excellent for commuting and for the environment. Then there’s the undeniable thrill of moving along at speed under your own power.

But now new research by US scientists suggests that when the training volume increases, cyclists enjoy an additional advantage over runners.

The science

In the study, scientists at the Appalachian State University in North Carolina compared the levels of exercise-induced muscle damage, soreness and inflammation in cyclists and runners who were asked to perform a three-day period of intensified training.

To do this, 13 trained long-distance runners and 22 trained cyclists were monitored for a period of 12 weeks.

Less inflammation endured                               Less equipment required

During this period, the runners and cyclists continued with their normal training, but during the fifth week, subjects from both the groups went to the lab and ran or cycled for 2½ hours for three consecutive days, which represented a significant increase over their normal training volumes.

Both the runners and the cyclists exercised at 70 per cent of their maximum oxygen uptake (ie a moderate-intensity pace) and had blood samples taken before and after the three-day period to test for markers of muscle damage, inflammation and immunity. The subjects also reported on the degree of delayed onset muscle soreness (DOMS) they experienced.

In a nutshell

When the scientists compared the two groups, it became very apparent that despite the identically increased workloads and durations, the runners’ muscles had taken a big hit compared to those of the cyclists.

The markers of muscle damage were 133-404 per cent higher in the runners compared to the cyclists. The runners also had inflammation markers that were up to 256 per cent higher.

Moreover, the runners reported a level of DOMS that was 87 per cent higher than their cycling counterparts.

When it came to immune markers, both groups suffered a drop in immunity of about the same magnitude.

So what?

If you’re a cyclist who includes a bit of running in your weekly programme, you’ll probably already be aware that hard running is more likely to induce muscle soreness than the equivalent intensity of cycling.

What this study shows, however, is that even at moderate intensities, running causes far more muscle tissue breakdown and inflammation than does cycling – something that partly explains why endurance runners generally have much weaker and less powerful leg muscles than their cycling counterparts and why runners are more prone to injury.

Another implication is that when adding running into a cycling programme, you should keep the length of your runs relatively short in order to minimise muscle tissue breakdown and strength/power losses on the bike.

This article was first published in the October 31 issue of Cycling Weekly. Read Cycling Weekly magazine on the day of release where ever you are in the world International digital edition, UK digital edition. And if you like us, rate us!

  • philip

    “Scientists discover that running is harder on the legs than cycling”…. now there’s a scoop. Who’d have thought it? Well, anyone who has run and cycled for a start! Save us from pseudo science 😉

  • Andy

    I agree with Dave. If you wanted a comparable ‘increased load’ the cyclists should complete three days of roughly 7.5 hours (three times the run time), after which they would probably suffer muscle ‘soreness’ but they still would not suffer the damaging effects of impact (even on a running band in a lab) that would accompany three consecutive days of 2.5 hour runs for anybody other than an elite marathon runner. Very few runners would undertake this sort of volume in three days, and it does make the comparison invalid: a 2.5 hour run is a serious long training run for an experienced runner; the same is not true of a 2.5 hour bike ride. Having said that, most people know that one great advantage of cycling is that is impact free, and, barring crashes, you are likely to encounter fewer injuries than serious runners.

  • Gabe

    Great point, Dave…I didn’t even consider that…

  • Simon Wood


  • Dave

    So the subjects “ran _or_ cycled for 2½ hours for three consecutive days,”and they were surprised when the runners had more muscle damage.
    Running 2.5 hrs for 3 consecutive days is a pretty intensive training regime – something not many serious marathon runners might do – whereas 2.5 hrs cycling a day at moderate intensity is an easy bank holiday weekend!
    To put it another way, a cyclist who takes up a bit of running to maintain winter fitness is unlikely to do 2.5 hr runs, a runner who starts cycling might soon be doing rides longer than 2.5 hrs