Rear deltoids

I am a mid distance freestyle swimmer that seems to suffer from pain in my rear deltoids and upper triceps. My recovery time from this pain is exceedingly slow, especially after long workouts. I essentially feel like my pull has no power behind it, and the soreness tends to linger for 3-4 days after certain workouts. Is this a normal area to have soreness in relation to a freestyle stroke? Do I need more warmup, cooldown, etc.? i am going through physical therapy and part of my exercises are for the rear delts. which apparently are weak on alot of male and female swimmers. my pull feels the same way also and i swim all strokes. probably some good strenghening exercises would work. i lifted before i got hurt and although i thought i was doing weights to strengthen this area, i wasn't . just a thought.

I am a mid distance freestyle swimmer that seems to suffer from pain in my rear deltoids and upper triceps. My recovery time from this pain is exceedingly slow, especially after long workouts. I essentially feel like my pull has no power behind it, and the soreness tends to linger for 3-4 days after certain workouts. Is this a normal area to have soreness in relation to a freestyle stroke? Do I need more warmup, cooldown, etc.? i am going through physical therapy and part of my exercises are for the rear delts. which apparently are weak on alot of male and female swimmers. my pull feels the same way also and i swim all strokes. probably some good strenghening exercises would work. i lifted before i got hurt and although i thought i was doing weights to strengthen this area, i wasn't . just a thought.