What are the best ways to improve my endurance and speed at swimming?

I am a serious swimmer, and I swim about five times a week. The fastest and easiest way to drop time is to perfect your stroke. Even Micheal Phelps and the like do not have perfect strokes. Also practice kicking, underwater kickouts, and turns.

improve your technique cross train (weights) can't guarantee you will shave off the time but if you've never had your stroke perfected, there is a LOT of time in there.

TRAIN TRAIN TRAIN! thats what i do. join a swimming club, like midbed, flitick dolphins e.c.t the nearest one to u, and train. im in a club, and i do 50m in 32 seconds, and im well under 16, though its tough. i train 6 times a week. if u dont want to do that, then u will simplyh ave to keep on going in and be pantient. :) you should be eating carbs, like pasta, to keep you going for a while. and for your technicke, make sure your allway kikcking, doing lots of dophin kicks off walls e.c.t hope it helps :)

It may sound hippie but it helped me. ive been swimming in very small swimming competitions for about 10 years. i recently need to shave, a bit life you, about 5 to 10 second off my time to qualify for the national swim meets. my coach suggested after exhausting extra practices didn't help, visualization. you will need a stopwatch you lie or sit in a quiet space and imagine yourself doing the task. imagine everything from getting changed to walking to the edge of the pool. as you dive in start the stop watch whilst your eyes are closed. imagine your stoke and the turns and of course the time and timer. as you finish stop the stopwatch. then look at the time. this should be close to your own time if done properly. do this every day for a little while and each time try to visualize it quicker (e.g. arms moving quicker, kicking faster...etc.) after a while your time near enough reflect the visualization. hope this helps

You probably weren't on a swim team with that time. The best thing I could tell you is just kick as hard as you can, remember to rotate your body, and pull the water as hard as you can. Technique isn't the most important in sprints, just go as fast as you can and keep your body straight. Don't pull your arms completely, but make sure that you're actually pulling the water. As for food and drugs, you don't need a special diet for 75m and stay off the drugs.

you have been swimming for years? 3 lengths in 68 seconds sucks. That is an average of slightly over 23 seconds per lap. Well..running won't help a bit. You need to improve on your technique. Go to youtube and find a video of an Olympian swimming. Right now you just need to do laps with efficiency.

Id go with treadmill for stanima and speed i would do weights.