In case you hadn’t noticed, barefoot and minimalist shoe running seems to have exploded in popularity (including my wife's recent run in the Wildflower triathlon wearing her Vibram Five Fingers, pictured above).

From Paleo and primal enthusiasts to the Barefoot Running Society (with nearly 2000 members), to crazy people trying to run across the country barefoot, barefoot running has certainly become a craze over the past several years – despite significant advances in shoe technology, enhanced shoe features like better cushioning or motion control, and even the advent of special fitness shoes.

But is barefoot running safe, or is this trend simply sending lots of excited, shoe-less runners to the sports medicine doctor with foot injuries? The answer is: it depends on your approach, and you’re about to learn why.

To decide whether barefoot running is safe for you, it’s important to understand the basic biomechanics of running.

Running involves two basic phases: a ground contact phase (in which your foot strikes the ground and maintains contact with the ground) and a swing phase (during which your foot is moving through the air).

Aside from perhaps a small amount of extra weight from a shoe, the swing phase is not as important as the ground contact phase when it comes to understanding how the presence or absence of shoes may affect your running gait, since the impact with the ground tends to transmit about 5 times your body weight through your leg – so let’s focus on that phase, which basically includes:

1) Contact: your leg decelerates and absorbs the impact from striking the ground

2) Midstance: your body weight shifts from the back of your foot to the front of your foot to prepare for leaving the ground

3) Toe-off: you extend your foot, ankle, and legs, and push off the ground

During this series of movements, your foot needs to absorb the impact of striking the ground, and also absorb your own body weight as you move over your foot, and this scenario can be very different when barefoot running is compared to running with shoes.

When you have shoes on, you tend to strike the ground closer to the back of your foot, which is called a heelstrike. But when you take your shoes off, or run in minimalist shoes such as Vibram Five Fingers or the Merrell Trail Gloves, you tend to strike closer to your midfoot or forefoot, and there are two significant mechanical things that happen when you make this change.

1) You take shorter strides when running barefoot. Running with shorter strides and higher frequency naturally reduces the impact forces on your foot – which you tend to not worry about quite so much when you’re wearing shoes. Fortunately, shorter strides also mean less impact higher up in your ankle, knees and hips!

Likely due to these shorter strides, barefoot running has also been shown to lower heart rate and rating of perceived exertion while increasing running efficiency.

2) You land with a slightly flatter foot when running barefoot. Since your toes are quite as “pointed towards the sky” when you’re running barefoot, since you don’t strike with your heel as much, this means that your heel and ankle undergo far less pressure and impact.

In addition, the skin on the bottom of your foot can actually do a better job sensing the ground when you run barefoot (called “proprioception”), and this may help the small muscles in your feet do a better job distributing load and lowering the force of impact in any given joint. In other words, running barefoot may reduce your risk of injuring your ankles, knees or hips.

On the other hand, shoes – in addition to being a powerful fashion statement – can protect your from sharp objects, extremely cold or hot ground conditions, or bacteria and germs on the ground.

Also, if you are overweight, have poor running form, have a weak core or hips, or have spent your entire life wearing shoes for most activities, then you’ll appreciate that shoes are designed to provide your foot with extra support and cushion to absorb the impact from landing and to keep your foot from moving excessively (e.g. overpronating) you’re running.

But even if you do fall into one of these categories, you can successfully transition to barefoot running if you go about things in a smart way, using the following tips for beginning to run barefoot, and staying injury-free as you keep barefoot running:

Take Baby Steps. Muscular adaptation to new activities takes about 4-8 weeks, so allow for at least this much time to transition into barefoot running or minimalist shoes, especially if you’ve worn big, fancy, built-up shoes your entire life! For example, for the first 4 weeks, you can simply use walk barefoot for 20-30 minutes each day and be sure to have your shoes off as much as possible, especially when standing at work or home. For the next 2 weeks, begin to run barefoot for very small distances on soft surfaces, like a few laps around a park or any easy jog several blocks around a soft track, just 2-3 times per week, and no more than 1 mile. Each week, gradually increase this volume, adding no more than 10% per week. After 8 weeks, if your feet are pain-free and you feel comfortable on soft surfaces, you can start experimenting with harder surfaces, paying very close attention to how your feet feel and whether or not anything hurts (which is a good clue that your feet aren’t quite strong enough yet for longer distances or hard surfaces).

Do Drills. As part of the short runs that you start doing barefoot, also train your body how to run with good form by including running form drills, such as playground style skipping, the toe-up drill or the lean drill. These drills will help ensure that you’re running efficiently and striking the ground properly as you learn barefoot running, and are a good idea to incorporate whether or not you’re running barefoot.

Feel The Ground. If you’ve been wearing big, bulky, protective shoes for a long time, then your foot may have difficulty properly sensing the ground when you run barefoot. So try incorporating “feel-for-the-ground” activities like standing on one leg when you’re brushing your teeth, standing on one leg while on a balance disc or balance pillow at the gym, standing on one leg for exercises like overhead presses, or even bouncing on one leg on a mini-trampoline a few times a week.

Get Flexible. One of the most common complaints among people who transition to barefoot or minimalist running is that their calf muscles and Achilles tendon feel tight or painful, and that was certainly the case when I made the transition to barefoot running. So as you make the transition to barefoot running, also work on the flexibility of the back of your legs by doing calf stretches and foam rolling for the back of your legs.

Get Strong Feet. If you’re worn shoes your whole life, it’s likely that you have weak feet muscles, since one of the primary functions of a shoe is to provide your foot with extra “muscle”, or support. While some of the balance activities mentioned earlier will help to strengthen your foot, I also recommend standing on one leg and practicing rolling your entire body weight from the outside of your foot to the inside of the foot and back, until your foot is tired. When at the gym, it can also be helpful to do cable kick forwards and cable kick back exercises while standing on one foot. If your tiny foot muscles start to burn and fatigue with these movements, you’ll know you’re conditioning your foot muscles.

Include Plyometrics. Your feet need to be conditioned to withstand the impact of the ground, since the cushioning of a normal shoe provides significant impact reduction benefits. Plyometrics are explosive exercises in which hop, bound or skip with one leg or two legs, and good choices for barefoot running preparation are side-to-side hops and single leg jumps onto a box.

Ultimately, if you rush out to purchase minimalist shoes, or toss your old shoes in the garbage and start running barefoot, you may have a high risk of injury if you launch right into your usual workout routine and running volume.

But if you make a smart transition, using the barefoot running tips in this article, you may find barefoot running or running in minimalist shoes actually reduces how tired your knees and hips are after a run or workout, and increases your enjoyment and feel for the ground during a run.

That was certainly the case with me, and I frequently head out for weekend 12-15 mile runs with nothing but my running shorts, my minimalist shoes and a smile on my face.

Do you have questions about how to start running barefoot? Leave them below and I'll be happy to answer!