If you're going the same distance on each, walking would be much more beneficial.. But I doubt you would go the same distance... It's a hard question to answer without specifics. Ie. 'Is it better if you ride the bike for 30 min with an average HR of 130, or walk for 1 hour with an average HR of 90?'
Because you can walk for 20 minutes, and bike for 20 minutes, and there is a HUGE difference. But if you walk for 2 miles, and bike for 2 miles walking is definatly better. Kind of a crappy answer, I know lol. If you give me a little more info I could probably be of more help
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