I'm a passionate runner, and always considered cycling as something fun, e.g. mountain-biking, but difficult to practice regularly. There's a lot of overhead in cycling, like the preparation, bike maintenance, dealing with city traffic, etc.
Anyway about eight months ago I bought a road bike and felt in love with it. Soon after that I discovered Zwift and that gave an additional dimension to the sport: practice whenever you want from home, with accurate power measurements and a way to socialise with distant people. That was a game changer.
In five months I cycled 1600 virtual Km and climbed almost 17 virtual Km. Meanwhile my running performance, instead of degrading, improved, and that surprised me.
Anyway what I wanted to write about is a great article I read, "Physiological Differences Between Cycling and Running". It's a review of articles published in that area. Some conclusions are very interesting.
In general it seems sports medicine is still inconclusive for many aspects, and coaches may still have an advantage by following empirical/heuristic approaches in comparison with research-driven indications.
But more specifically, some notes from the conclusions:
- For the same person, VO2max depends on the speciality (i.e. runners achieve higher values on treadmill than cycle ergometer)
- There seems to be more physiological transfer from running to cycling than the other way around
- Pedalling cadence impacts the metabolic response during cycling, but also during a following run (at least in the short term)
- The Lactate Threshold is lower for athletes when not practicing their speciality, i.e. the Lactate Threshold depends on the training method
- Both female and male are impacted in the same way when comparing VO2max for running and cycling
- Triathletes have similar max Heart Rate when running and cycling, again pointing to the importance of the actual speciality used in training
- The position when cycling makes it harder to breathe
and probably other important elements that I wasn't able to fully grasp.