I’m 5’7 and weigh about 165, should I go for a med or small?
I would advise going a size larger, depending on how you like your pants to fit and whether you typically have 'quad fitment issues.' I am 6ft 225lbs and a large is tight on me in the quad/back area.
Can you fit a phone into the pockets?
Yes, no problem to fit a 5’5 cellphone,wallet into the pocket.
Are these training joggers stretchable?Breathable?
Yes very stretchable and soft!Breathable yes. I'll do 30 minutes treadmill, followed by 15 minutes bike, followed by 20 minutes weight teaining and no problem.