If I were raising teenage boys today. . . oh, wait! I am! What I’ve learned from raising mine, watching others and reading is that big boys need to use their large muscles every day, prove themselves (be competent at something), and feel loved.
For most of us, the days of plowing fields, building fences, and taming horses is the stuff of storybooks. But, the need for boys to be involved in activities like that is still current. They need to use those muscles in large ways. In one homeschool resource I read, the mother said that everyone in her family ran on the treadmill for 20-30 minutes every day. It helped settle them in to study. The benefits of exercise have been widely documented, including increased ability to concentrate and increased feelings of well-being. In prison populations, studies have shown an decrease in acting out and aggressive behaviors when inmates participate in a regular program of aerobic exercise.
So, how to harness those powers for our sons? A treadmill, elliptical trainer, or stationary bike provides access to aerobic exercise regardless of weather. On good weather days, running is a good option for some. A friendly basketball competition works if you have a couple of guys. Ideally, a sport that father (or uncle or mentor) and son do together would be part of the “workout package”. It allows them to challenge themselves and each other, to bond, and to get/stay fit.
A second, important part of the physical activity package should be a large punching bag. It’s an excellent way to work off energy or anger kicking or punching in a beneficial way. If your son has anger issues, particularly anger management issues, I’d get a bag ASAP. We use a bag like this. 
The one we picked up secondhand has worked very well for us.
IMPORTANT: Be sure to use gloves whenever punching. Injuries are never a help! 🙂
Most workout equipment is available secondhand; even new, at full-price, the investment is well worth it.