One thing I learned the hard way is to wear non-cotton shirts as cotten chafes wicked!  I was running at about mile 10 I felt like my nipples were on FIRE!  Of course, once those bad boys are stimulated unfortunately the keep looking out only to get a beat down. 

 

TIP:  Wear tape, nipple guards, Vaseline or "Body Glide".  Also, wear a tight non-cotton running shirt.

 

Details & Pricing:

Bodyglide Skin Formula - this is non-greasy (unlike Vaseline) and does not fall off like tape

Nipguards Runners Nipple Protectors - these are smaller than large patches of tape and don't fall off

Champion Men's Sprint Tee - non-cotton goodness