Does mountain biking ie difficult stuff on a bike made your bum big?

[passmyglassplease]

Just interested to know, I have recently taking up mountain biking and have notice that my derriere is getting larger!

so, is it down to all that pushing my bike up hill I do, or am I just getting fat

And if it is the bloody mountain biking how to minimise any further damage?

Shouldn't do. I used to cyle off road alot and didn't notice much shape change. I may have lost a couple of pounds and my legs were firmer but not massively so.

It won't be long before you are cycling up the hills, not pushing the bike though. Your fitness will improve quite quickly

Try doing bum weights lunges and squats - that may help perk your bum up

The effect of cycling on the derriere does depend on the riding position, as well as frequency. I have certainly noticed that since getting a granny upright bike to commute on (half an hour to work each way so at least an hour of biking a day every day), my bum has got a lot more toned and sort of lifted ifykwim.

Previously I used a hybrid to commute on, which is much closer in riding position to a mountain bike, and the gluteus didn't really get any meaningful exercise at all, so I would suggest that mountain biking may not be making your bum bigger, but it won't be making it smaller either.
If you were doing good exercise for the rear before and have now replaced it with mountain biking (and if like me, mountain biking means a good excuse to eat lots of chocolate and high calorie snacks and then go for a beer or two afterwards), perhaps it's indirectly doing so...

HTH