Hi, I bike about 20 miles a day. So, my question is which burns more claories and gains more muscle, biking 20 miles(avg. 15 mpg) both uphill and downhill or running 3 miles(avg. 7 mph)?
well running you burn more calories and it will build a lot of muscles but biking really builds muscles in your legs especially if you're going uphill on your bike
and it's alot easier on your body, with running you get the aches and pains and sore knees, hips, feet, etc. biking has very low impact, not to say you won't be sore if you do alot of biking but there will be no permanent damage.