After a day of biking or hiking I have two distinctive bulges in my groin but no discomfort from them. After resting they go away? What next?

See your doctor. You may have hernias. Hernias develop when intestines bulge through weak areas in the abdominal wall. They can be painless and commonly "reduce"/resolve with laying down. You should try to see if you can get in with your doctor after hiking/biking so s/he can see the bulges. Here's a link to more info: http://www.Mayoclinic.Com/health/inguinal-hernia/ds00364.
See hernia surgeon. A hernia is a hole in the abdominal wall through which the inner lining of the abdominal cavity stretches, creating a sac. It is not uncommon to feel a bulge when exerting oneself , such as coughing, lifting, etc. Not all hernias require repair, yet this is best determined following consultation with a hernia surgeon.