This is why I love our suspension trainers!
As you, a dedicated fitness enthusiast who also diligently reads GQ, are no doubt well aware, the only exercise you really need to build a Gronkowski-esque chest is the trusty ol' push-up, which requires only a few square feet of semi-cleared floor space to complete. But what happens once I have mastered the push-up?, you may be asking yourself. However shall I ensure that my fitness journey does not thereafter come to a quiet, prone end?
Many gyms now prominently feature "instability devices," including Swiss balls, suspension devices, medicine balls, wobble boards, and the like. (Actually, many of these contraptions are small and portable enough that you might consider stashing one for home workouts, too.) When incorporated into a familiar movement—for example, a push-up—these things are supposed to activate hard-to-train muscle groups in ways that performing the exercise on terra firma simply can't replicate. A recent study conducted by researchers in Spain aimed to shed some light on which of these myriad devices does the best job at making push-ups into a more challenging full-body workout, and which equipment you should feel free to leave to your less-informed fellow gym-goers.
In the experiment, subjects performed push-ups on the floor; on a wobble board; on a stability disk; on a fitness dome; and using a TRX suspension trainer. Although the researchers found no significant differences between floor push-ups and unstable push-ups when it came to shoulder activation—the muscle group you're probably used to training with a push-up—their findings for the rest of the body are more interesting. Each of the instability devices yielded activation levels in core, lower back, and leg muscles that were significantly higher than floor push-ups, and the TRX suspension trainer easily outpaced its counterparts in the latter two muscle groups. Thus, although all the studied options help make the push-up into a better core workout, only the TRX trainer really brings the lower body into it, too. The researchers hypothesize that the TRX device, which entails completing the movement while suspended in mid-air, requires users to exert more effort to control their body than when the ground is helpfully pushing back beneath them.
It may not be flashy, but science says that the push-up is still one of the most dependable exercises in your regimen's arsenal. Once you're in need of an additional challenge, ditch the other stuff and wait for a turn on the TRX. Make sure you know how to get in and out correctly first, though, and consider using a spotter until you've got the hang of it. An efficient, efficacious, full-body push-up workout is great, but a smashed-up face and badly bruised ego are decidedly not.