I haven’t been swimming much lately but the couple times that I have, my elbows have started to hurt. It’s not excruciatingly painful, but definitely irritated/sore between the medial epicondyle of my humerus and olecranon process of my ulna. The only other time I’ve had this happen before, it’s been when I’ve swum like ~10k workouts, and I’ve reasoned that it’s an overuse thing. Right now, I’m swimming in open water 1-2x a week, 2-6k a time (depends on who I can coerce into going along with me 
so it doesn’t make sense for it to be an overuse thing?(right?). Is it possible that this is a stroke mechanic issue, and if so, any ideas as to what’s wrong with my stroke?
I’d appreciate any ideas. Swimming’s supposed to be the thing I can do as much as I please and not get hurt!!! This is SO NOT FAIR!
Describe the type of pain… Does it radiate anywhere? When does it start to hurt? Does it hurt after you stop? Dull or sharp? tingling? Does it hurt with any movements in particular? Does it hurt when doing things non-swimming?
Irritation. As if there is a frayed cord rubbing on the bones.
Does it radiate anywhere? no
When does it start to hurt? Tonight - after half an hour 
Does it hurt after you stop? if I stop when it starts to hurt, then it goes away. If I keep swimming while it hurts, then it stays for a day or so.
Dull or sharp? a mix of both but leaning toward sharp
Tingling? no
Does it hurt with any particular movements? well, freestyle. I didn’t try any other strokes but I imagine they’d hurt as well.
Does it hurt when doing things non-swimming? no.
ideas?
Sounds like golfers or tennis elbow. Both cause inflammation of connective tissue around the elbow due to over-use or bad mechanics.
See a physio!
Yes, it is probably your stroke mechanics that is causing it. I would suggest trying other strokes/drills in the meantime to minimise the amount of free you do. You obviously do a lot of swimming, so I wouldn’t be worried about too much loss of form. Kicking etc too.
One test for this is to get a table or something at your shoulder height, and place you hand on the level without the arm, with the shoulder above the elbow and the elbow above the wrist like you do in the catch phase. Press down, and note any pain. Now do the reverse, pressing up in the same position. Again note any pain. One test suggests golfer’s elbow, the other tennis elbow, but I can’t for the life of me remember which is which! Sorry!
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