I didn't know I worked my abs and back that hard

To break up the monotony of my swim, last Friday I stopped every other lap and grabbeb the back stroke starting bar while facing the pool. Then I did 30 hard dolphin kicks. Since my body was not able to glide away and lessened the pressure, the kicks were much harder than normal dolphin kicks.

Well, I did 15 sets of 30 dolphin kicks. My abs and back were extremely sore afterward. No pain mind you just sore like how my legs feel after a hard long run. I think I've found my favorite abs and back workout :) At least watching the water rushing away from my kicks gave me the satisfaction that I'm expending the calories any way.