Hi, I love to hear from other swimmers. I'm a former competitive swimmer (last race was 30 years ago!) and now do it as part of my overall routine. In the beginning of my weight loss it was the only activity I did and I lost weight quite easily doing it. Now I use it to balance all the impact activities I do and it's espcially nice for arms - toning and strength. So my opinion is that swimming can make a real contribution.
I have a bit of advice, someone mentioned shoulder pain. I had a problem with my shoulders as well (never when I was young, but now...). The pain was a dull ache, non-specific. I learned that the shoulder muscles have to work together to hold the bones in the right places, and when some muscles are weaker, etc., there can be an imbalance that causes pinching, etc. Sometimes the joint seems to almost pop in and out a bit. Apparently this is pretty common. The repetitive motion of freestyle seems to be my problem. A good way to avoid it and what has worked for me is to do all the strokes rather than just freestyle, and to strengthen my back shoulder muscles with weights. So you might keep an eye out for this - build up gradually and let your system adjust to more yardage (I of course did not pay attention to this idea, and well, it would have been better...)
You might also look into doing interval training - rather than just laps - as you go along. Like they say with running, etc., it conditions you well and helps with calorie burning (and the boredom factor of just going up and down the pool.
I also had plantar fasciitis for some time when I was heavier. I endorse the shoe advice others have been giving. Even now I have some flare ups, and swimming helps ( I think the flexing of the foot?) Another thing - I've had shin splints and swimming was painless for me with them while I was recovering. It also helped me build strength in my left arm after a broken elbow. (Sounds like I'm a walking accident, really, I'm not!) Anyway, I think it's great to have swimming in your repetoire of exercise.
I also really think it has helped me avoid lots of muscle pain from doing weights and other cardio. Sometimes I swim after a class, just a little,, and the flowing nature of the exercise really seems to help me recover.
Good luck with it, I just love to read that others are swimming. At my gym, there are not many swimmers compared with runners, etc., so usually there is not a lot of chat about it. It is great to have it here and heaer what others are doing!


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