The Final Steps to Minimalism
Phase 3 starts at the 'Zero Heel Drop/Minimal Cushion' stage of Phase 2, so the next step is to raise the bar by losing the shoe. Now I should warn you that this is the stage that I'm currently at, so the actual barefoot thing is quite new to me as well. I will try to provide the most reasonable advice available, but I haven't personally tested it all... yet!Assuming that you've become proficient at running light on your feet in a minimalist shoe, and have built up some sort of endurance for the activity, the most difficult part of this stage will be strengthening and adapting the soles of your feet. Not in a muscular way, but in tolerance-to-sharp-or-rough-things kind of way. And just as you did in Phase 2 as you transitioned to the right along the Minimalist Progression Scale, you'll want to start with extremely short barefoot runs (0-2 min). Please be mindful of the conditions outside when attempting this - if there is ice and snow your feet may freeze, if it's hot and sunny you could burn them on a hot side-walk; be smart about it.
You may find your feet feel quite warm on the soles while running and later may be a little tender to the touch. This is normal and is the reason you're starting out slowly, they just need time to adapt. Ice baths for your feet can feel really good! Also, fellrnr.com has a great section on ways that you can help toughen up your feet more quickly.
Going Further - Limits of Form
You may not want to go all the way to barefoot running and that's totally OK! But, no matter where you choose to stop along the horizontal axis of the Minimalist Progression Scale, you'll likely want to keep increasing the distance you're running.While doing this, be mindful of the effects of fatigue on your form. In my experience, my form would break down 15-20 miles into a marathon, despite training exclusively in Vibram Five Fingers for 2 years, and that is when injuries can happen. Now this may be farther than you might try and go in your minimalist shoes, but the lesson will be the same; form breaks down with fatigue, and injuries are more likely at that point. Which brings me to my next point:Train Low, Race High
Training in a minimalist style is great since you can focus on maintaining that proper form and you can adjust your run length to reflect how you're feeling. Racing on the other hand can present issues in terms of maintaining form. So, one option is to train in your minimalist shoe (or barefoot) and then use a slightly more cushioned shoe for your racing. This allows you a little give in terms of your form while you race and will provide that extra little bit of comfort. Traditional racing flats are a good option as they have minimal heel drop but still have enough cushion for when you're fatigued.Staying Balanced
With long-term minimalist running certain muscle groups can become weaker than they would with traditional shod running, most evidently quads, glutes and tibialis anterior. This is not normally an issue so long as you continue running in a minimalist style, but if you're like me and you need to go back to a more cushioned shoe, say for trail running, you can have problems. So even if you don't plan to switch back, it is smart to do some form of cross- or weight-training, targeting the quads, hips and glutes.I hope you've enjoyed this minimalist and barefoot running guide and that it has been somewhat educational for you. The only thing I can't emphasize enough is to build up to your goals slowly and deliberately while taking precautionary steps as needed to avoid injuries and other issues.
Run free!