If you only had 30 minutes to workout...

I think I would run, too.

I agree that you could get the best workout in a 30min run vs a 30min swim or ride.

I would likely run too but I'm not sure about the best workout part.  In 30 mins, I can beat myself to a pulp both in the pool and on the trainer.

Yeah...but not all of us can swim 2500 in 30 minutes...

Most likely run. My shortest runs are generally 30 minutes; whereas my shortest bikes are close to an hour. I wouldn't do run speedwork because I need to warm up for at least 15-20 minutes first. At most I might do 30 seconds of strides every five minutes during the run.

I'd swim if it was a time when the pool was available, because I could. The only times I can reliably do swim training--as in not share a pool with screaming, dive-bombing kids, are 4:10-5:00 on Mondays and Thursdays, and 2:30-5:00 on Saturdays. So if the 30 minutes fell in that time window, I'd swim. What I like to do for those short times is a continuous swim, or long repeats with a short break, where part of each repeat is hard and part is steady, "endurance" pace. For example, 3 X 400m with the first 25m of each 100m hard, or 4 X300m with the first 100m of each 300 hard. Either that or the old standby--about five minutes warmup, 10-12 X 100m on 1:50, five minutes cooldown.

Um... yeah.  I mostly do sprints and a 30 min run or swim is not unusual.  I wouldn't turn my nose up at a 30 min bike ride, for that matter.  Heck I'm training for a HM now and I do a lot of 30 min-ish runs.

Depends when it is.

I do the bulk of my swimming in 30 mins at lunch. I'd rather swim than bike/run as it's less of a sweaty cooldown afterwards and I can cram it into the day as opposed to losing a gob of time before/after work to swim.

If isolated bang for buck though, it's running bar none for a high quality 30 mins. I'm convinced that I can stay near the FOP in duathlons just by running this much.

Run

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