Peter Attia· MD
when you do work or do when you do produce a certain amount of power obviously two there are forces involved and there is velocity involved these forces requires a certain amount of recruitment of muscle fibers and these muscle fibers at a certain point will actually start to cause vasel constrictions so they actually start squeezing off the blood supply they normally Act as a pump they actually help pumping blood around in the body promoting uh preloading but the interesting thing is that we do see that where you also get in the area of anerobic tral is actually where you are starting to come to the point where you're squeezing off the blood flow as well in the muscles and this happens around ball Parish obviously there is a fairly large Ranger but ball parkage around 30% of your one RM so there you got another way so you should never experience that on a bike right because in theory you know it's hard to imagine you could ever come close to 30% of a 1rm force on a pedal stroke Could you um that's true yeah that's true well well I mean maybe there's an extreme moment you're you're at a 16% grade or something like that I guess it's possible huh yeah for sustained efforts obviously you can for short efforts you can get very very close but but but but but for sustained ones yes I would agree um but coming back to coming back to uh uh running versus uh running versus the bike uh so which was the let's say the place where you where it started um normally I would say that yes in in running uh you would at least a submaximal efforts have a higher uh view to Max the only thing is that we see that in people that are less say somewhat balanced train so they do they spend I say a fair bit they spend some time on the bike they spend some time on running then normally there are more muscles involved for a longer duration in cycling than it is in running