Here are some sample photos of what nipple chafing can do.
There are plenty of ways to combat nipple chafing. Some people use lube (Body Glide or Vaseline are popular choices). Some people use bandaids. I've even seen guys cut holes in the front of their shirts.
Buying shirts made out of a smooth, performance-designed material (tech shirts) is a good start. But I've found that any run longer than 8-10 miles requires some kind of protection. So far, I've been happy with a product called Nip Guards. I've been using them for years and they definitely solve the problem.
Nip Guards are little stop-sign-shaped band-aids that have a ring of adhesive foam around the outside that actually raises the band-aid off of your skin. They kind of cover your nipples like little band-aid 'cups'. They might look a little odd poking through your shirt, but they definitely do the trick and it's better than wanting to cry every time a light breeze hits your bloody nipple.
For anywhere else on your body that rubs when you run, I recommend Body Glide. It comes in a stick that looks like deodorant and you just rub some on any place that might chafe. A stick of this stuff lasts a long time and it's pretty inexpensive. It's amazing how much a long run can be affected once you start to chafe and it becomes painful. A little bit of Body Glide and you have one less thing to worry about.
Goal For The Day: Rest.
Distance: 0.00 Miles.
Notes: Gorgeous weather today. Tomorrow's Long Run should be great weather too. Six weeks to Race Day!
Daily Miles: 0.00 Miles.
Run - 346.65 Miles.
Bike - 144.45 Miles.
Swim - 10,050+ meters.