If you really want to target the three-headed muscle at the back of your arm — the triceps — you need to bring out the heavy artillery. The triceps are composed of a high percentage of type II muscle fibers (67.4%), and all three heads of the muscle are fully activated only when the resistance is high.

Once a solid strength base is established, those seeking well-developed triceps should avoid the common mistake of using light weights for high reps — a trap many females fall into.

The rectus abdominis (your “six-pack” muscle) is another area often trained incorrectly. It too contains a higher percentage (over 50%) of type II fibers and responds better to heavier loads rather than endless reps of low-intensity work.

Bottom Line

If you’re tired of your arms flapping in the wind, ditch the triceps kickbacks with pink dumbbells and start doing multiple sets of close-grip bench presses and parallel-bar dips. Use a challenging weight, train them often, and you’ll have those arms shrink-wrapped in no time!