Fly endurance

The above are all good suggestions. And you should also have a coach look at your technique. If you want confidence that you can do a straight 200 fly, you can try the following (I can't remember where I saw this): -- do a 200 where the first stroke off each wall is butterfly and the rest is smooth, easy freestyle -- once you feel you can do that comfortably, add another stroke off each wall -- rinse and repeat The last lap of a 200 fly will be 8-10 strokes for many people, so it doesn't take that long before you are up to a straight 200. Again, this exercise isn't necessary for training purposes, just to convince yourself it is possible. Broken 200s fly are also a possibility. Break them at the 50 with plenty of rest to start with (30 seconds? More?) and over time gradually decrease it until you can do it with 10 sec rest without too much problem. A variation on this -- one that feels more like an actual 200 fly race, IMO -- is to take decreasing amounts of rest on successive 50s. For example: take 15 sec, then 10 sec, then 5 sec after the 1st, 2nd and 3rd 50s of the broken 200. (You don't need to do a lot of these, and take plenty of rest between efforts if you do more than one.) Fly drills are less painful ways of building fly endurance. Try the "single-double-single" drill, where you do multiple cycles of right-arm/double-arm/left-arm/double-arm butterfly. This drill is not as tiring as regular butterfly but it should help build fly endurance. Do a set of (say) 5 x 100 fly drills with plenty of rest between.

The above are all good suggestions. And you should also have a coach look at your technique. If you want confidence that you can do a straight 200 fly, you can try the following (I can't remember where I saw this): -- do a 200 where the first stroke off each wall is butterfly and the rest is smooth, easy freestyle -- once you feel you can do that comfortably, add another stroke off each wall -- rinse and repeat The last lap of a 200 fly will be 8-10 strokes for many people, so it doesn't take that long before you are up to a straight 200. Again, this exercise isn't necessary for training purposes, just to convince yourself it is possible. Broken 200s fly are also a possibility. Break them at the 50 with plenty of rest to start with (30 seconds? More?) and over time gradually decrease it until you can do it with 10 sec rest without too much problem. A variation on this -- one that feels more like an actual 200 fly race, IMO -- is to take decreasing amounts of rest on successive 50s. For example: take 15 sec, then 10 sec, then 5 sec after the 1st, 2nd and 3rd 50s of the broken 200. (You don't need to do a lot of these, and take plenty of rest between efforts if you do more than one.) Fly drills are less painful ways of building fly endurance. Try the "single-double-single" drill, where you do multiple cycles of right-arm/double-arm/left-arm/double-arm butterfly. This drill is not as tiring as regular butterfly but it should help build fly endurance. Do a set of (say) 5 x 100 fly drills with plenty of rest between.