How to determine if you should be slipping on these super light sneakers, or if you should just lace up like normal

Adidas by Stella McCartney

There's a lot of hype around minimal running shoes (MRS). Some people swear by them, claiming they've totally changed their running experience, while others find them both painful and unnecessary. With new research cropping up all the time on their respective benefits and drawbacks, it would seem that exercise scientists are more intrigued than ever on how different kinds of sneakers can have varied effects on both your body and your performance. (If you're ready to give them a try, check out our picks for minimalist running shoes that will fit any style.)

In a study conducted by Hong Kong Polytechnic University in conjunction with Harvard Medical School, researchers found that training in MRS increased runner's muscle mass and strength in the feet and lower legs. The study divided 38 runners into two groups: one who wore MRS for 6 months and another who wore traditional running sneakers for the same amount of time. Both groups completed the same training program, which included running, leg strengthening moves, and balance exercises. Everyone had their right leg MRI'd before and after the 6-month period.

The results were pretty clear: The runners who wore MRS had increased muscle mass in their lower leg and foot, while those who wore traditional running shoes didn't experience any major muscle mass changes.

The study authors say their findings could have promising effects for people with foot injuries, suggesting that an exercise rehabilitation program using MRS could help regain muscle mass and strength in that concentrated area. But what if you're just a runner who's hitting the pavement on the regular for fitness (and pleasure)? Should you be wearing minimalist running sneaks, too? Bob Coll, a competitive long distance runner and owner of the Eugene Running Company, says not necessarily.

"[MRS] are a valuable tool for any serious runner to aid in strengthening the foot and lower leg," says Coll, as atrophy (the deterioration of muscle tissue) can happen if you're "under-utilizing the foot's natural range of motion and fully intended biomechanical range." The thing is, because you've been wearing shoes your whole life, you can't just permanently swap out your nice cushy sneakers for minimal shoes all at once. "Runners shouldn't buy a pair of minimal shoes and immediately use them for all their running," he says. "The orthopedic stress would likely be too much and the risk of injury increased. The appropriate plan for most runners is to initially integrate MRS on shorter runs, switching back to their traditional shoes in subsequent runs to allow their muscles, tendons, and bones to adapt to the new stress." Focus on gradually adapting your body to MRS, and try them out on various kinds of runs-long runs, hill climbs, sprints.

Coll also warns that there are certain drawbacks to MRS that might make you think twice about wearing them all the time. Most runners run on hard surfaces like roads and sidewalks, and more and more people are challenging themselves to complete marathons, triathlons, and other road races, which push people to the edge of their breaking points, he points out. "Face it, most of us aren't full-time professional athletes, and while many of us are very fit, we generally have lives that require career, parenting, and family obligations which place restrictions on training and recovery." So giving it all you've got in these big races on hard surfaces requires a little cushioning and support for most people, he says. In other words, for a man-made race, your body may need some man-made help in the form of arch support, shock absorption, and you know, some space between you and the pavement. (In the market for a new pair of running sneakers, cross-trainers, or studio shoes? Start shopping our favorite new sneakers for this year.)

And what about sneakers that offer so much support that they look like platforms? Coll says they definitely have their place on the road too. "Maximal running shoes with very high midsole volumes and low heel offsets have become increasingly popular over recent years and have gained acceptance in the general running population," he says. "Some runners report the extraordinary cushion has prolonged their running careers and allowed increased activity as they age." If a pair of shoes can potentially allow you to add years onto your running career, that sounds pretty good to us. (Yep, here's how you can keep running into your eighties.)

So here's the bottom line on MRS: They're an awesome training tool for those who want to increase foot and lower leg strength, but you need to be careful about when and how often you wear them. For most people, they will require some transition time and can't be worn for every single workout or race. As always, pay attention to how you're feeling and listen to your body.