Sometimes the best offense is a good defense. I know that sounds like a cliché, but it's true. If you're anything like the 20-year-old version of me, you probably believe that every workout has to be a record breaker and that doing more each time you set foot in the gym is what yields the greatest results.
While this kind of enthusiasm is inspiring, it reveals a lack of experience. Not only is more not always better, but often more is impractical. Dedicating 15 focused minutes to your arm training could be a whole lot better than spending lots more time going for some major new PR.
Why 15 Minutes?
Why train your arms for 15 minutes instead of the usual 45, 60, or even 90 minutes? You may have only a few minutes to spare. Shit happens. Things come up. You might normally dedicate an entire training day to your arms, only to find yourself overwhelmed with work, family, travel, or other real-world obligations. You need to train arms regularly, but it's foolish to sacrifice chest, back, shoulders, or legs just so you can spend your entire training session on one smaller body part.
Also, if you do a regular workout, you're already giving your arms indirect but significant stimulation from your chest, back, and shoulder training—assuming you're hitting them with adequate intensity. Fifteen minutes of arms at the end of these other workouts might be all you need. I'm not asking you to do squats for 15 minutes straight. Even if you're spent from your workout, you should still be able to get in a short arm workout—unless you're training with Tom Platz's legendary intensity!
What Results Can I Expect?
What you accomplish in 15 minutes depends on you. Maybe you've been beating the hell out of your arms week in, week out for years. If so, this short training might produce new progress. Hell, I've seen people's arms grow from not training them directly at all. So, even after just a quarter of an hour, there's a good chance yours will improve, too. At the very least, I'm confident you won't lose muscle.
For many people, the smart play might be to do a short workout rather than no workout at all, just so you won't go backward. Ten years ago, I would sooner have missed a workout altogether than not do my full routine. That was the wrong way to think about it. Something is always better than nothing. Just don't make "something" your new standard.
When Should I Employ This Approach?
I'm not saying you should do this short workout every week for the rest of your life. But if your arm training has grown stale, you're short on time, or your progress has stalled, try this short workout for a week or two straight before going back to more traditional training—just to see if switching it up changes anything.
If there seems to be a positive result from adding this workout, do it more often—maybe try three weeks in a row. If you can't do your full arm workout and are thinking about skipping arm day altogether, throw this in at the end of chest or back day, or after you do shoulders. Don't miss arm training altogether just because you can't do it the way you normally would.
How Do You Train Arms In 15 Minutes?
It's pretty simple. All you need are two movements: one for biceps and one for triceps. Compound movements can work, but you need to be able to work your mind-muscle connection to really focus on your arms. I tend to favor isolation movements because their impact on my whole body is much less than compound free-weight movements, so I'm less likely to slow down from overall fatigue.
When 15 minutes is all you've got, you need to maximize time under tension. That means no rest time between sets. None. Begin the first biceps movement using a weight that'll make it a struggle to get 25 reps. Immediately follow it with the triceps movement in the same rep range. As soon as the triceps set is complete, go back to biceps and begin again. Go back and forth over and over again using the same weight, completing as many reps as possible each time.
Don't hesitate to incorporate some rest pauses for the sake of getting every last rep you can. If you have a training partner handy, force reps for each other.
In short, the goal for those 15 minutes is to go all out! The pump is going to be crazy, fatigue will set in, reps will drop…and that's perfectly normal. Just keep going and complete as many reps as you can on each set.
Less time spent training can sometimes yield unexpected results, especially when the weight you use for your 15-minute workout is lighter than normal. In the past, I would have said the best offense is a hard-charging offense. And true as that can sometimes be, at other times you need to pick your battles. If your arm progress is stale, or if you risk missing your arm training altogether, then you have nothing to lose by trying this approach. Give it all you've got for those 15 minutes, and you might just learn something new.