Trek Mountain Bike Shirts

How can I properly clean my t-shirts?
I don’t overfill my washing machine and I wash on “40 degrees, synthentics” using biological washing powder.
But some of my t-shirts still come back a bit smelly under the armpits, even after washing. I am not a stinky person, but it’s the shirts that I do a lot of sport in (hence I sweat into them loads) that I can’t seem to get the armpit smell out of.
For example, there was one t-shirt that was quite new – I did an all-day mountain bike trek in it, sweated my nuts off (you know – the kind of sweat that goes totally rank after a day in mud, sweat, bike oil, etc, etc). I ended up washing it twice, by itself, with pre-wash and extra rinse, and it still smelled under the armpits, so I threw it away.
Disgusting, I know, but any tips will be much appreciated.
its your antiperspirant that making your clothes smell because you don’t like to smell i bet you put loads of deodorant on and then it rubs on your clothes, you could try a different roll on but its locking in your clothes locking the smell sorry i’ve not been much help but you could try doing without you probably don’t smell as bad as you think
Jersey Shore Meets The Underground Strength Show

