Exercises and 'sets' -> how long do you wait between each set?
 

Ive always been a little confused on this
For example when dumbbell exercises, youre supposed to do 3 sets of 10-12 reps. But how long do you wait between each set? I just do one set on an arm, then change arms for the next set. Am I supposed to just wait a few seconds, then go again on the same arm?

Also, are 'sets' preferred compared to just doing reps until exhaustion? For example, I often can still complete my very last rep on my last set without feeling that my arm is about to break off if i use the set method, but doing 25-30 reps in a row takes my arm to exhaustion. Which is better?

30 - 60 seconds before the blood flows out of the musle if you are looking to build mass.

yea no more than a minute. you wanna keep your heart rate going and not let yourself cool down too much.

Are you trying to tone or build mass? if you are going for bulking and you feel the last reps are not doing much - you need to add on the weight.

you should barely be able to do the last rep. going to failure is the only way to get bigger. Proper nutrition is critical for growth

always 75-90 seconds... except for situps/crunches, 20 secs max, 4 reps of 20

thanks all

What the other guys said. ^
15-60 depends on what your going for and how heavy your training

so basically it is perfect to do a set on one arm, switch over to the other to do a set, then go back?

no or very little wait between sets, between exercises, as long as it takes to get a few sips of water normally

Depends on how much load you put on your muscles.

Have you seen the average webmaster? Go to a bodybuilding board. :)

2 minutes max.....

if your arms arent tired at all then you need to lift a heavier weight... also, work on the 'mind-muscle' connection. It is possible to do a dumbell curl and not really use the target muscle (bicep) effectively