What other supplements should I take?

Just want to make sure you understand you're at a cycling forum.

There are a multitude of bodybuilding forums "out there" that can assist you with your goal of adding muscle mass. 99% of cyclists are more concerned with reducing mass - be it muscle or fat...Personally, I got an extra 15-20lbs of upper body muscle you can have for absolutely nothing - heck, I'd pay YOU if you would take it off my hands...😄

A good diet and a good training regimen. Both are a lot cheaper than all that other [censored].

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Some skinnier riders who need to gain mass, either simply to look better or to make themselves stronger on the bike in addition to hill repeats would benefit from controlled doses of creatine, whey protein after rides and more professional supplements. Of course any idiot knows that every body is different and many people suffer from deficiencies or need all the help they can get to get stronger. I am currently trying to gain pounds on the bike to be more powerful and more importantly to help gain muscular resistance (it's amazing how zapped the legs get after 2 long pyrenean climbs such as the somport followed by marie blanque after which my legs normally quit. I have learned the hard way that doing hill reps aint enough and 2 months ago sarted doing weights and taking whey protein after and consuming small protein bars during rides. This has all helped me ride further and faster but more importantly after long climbs at over 20kph average, my legs are less likely to give up or cramp.