This is extremely prevalent in the act of running. Modern running shoes are designed so that the runner is making first contact on the heel and rolling the foot over to move. They have it completely backwards! Look at an infant and you will see proper movement patterns. When they first start to toddle they will lean forward and gently fall onto the ball of the foot as they move forward. Using forward momentum to move through space. While on the opposite end of the spectrum we look at a runner who is extended the leg completely, landing on the heel, and then pushing off of the ground to move forward. Not only is this style of movement harder on the joints, but it is using up so much unnecessary energy to simply move forward.
Strength training is also improved by going barefoot. The chain of events in any type of movement start at the base and work up. Take for instance a simple body weight squat. You push the butt back, squeeze the hamstrings and glutes, and drop down into a squatting position. The movement is reversed by pushing away from the ground and back up. When a barefoot is solidly planted the ability to push and activate muscles becomes a much simpler task and you can feel all the muscles activating properly and make adjustments as necessary. When there is another layer of rubber, air, and/or gel in between the ground and the foot there becomes room for error. You can't feel as well if the heel is staying planted. If you're coming up on one side or the other. Whether or not you're pushing out on the sides of the sole. The problem is an opening for more interpretation without knowing. The foot was made specifically for these types of movements without a middle man, so why not allow it to do so? The flexibility that can be gained will also help greatly in every day movements. When the shoe is gone greater ranges of motion are achieved, and concurrently with it flexibility. The joints and ligaments stretch out and get stronger allowing for ease in movements that weren't possible before. This makes for gains in strength that also weren't possible before.
Lastly, I would like to touch on the idea of injury prevention. Barefoot training will undoubtedly will help stave off injuries over the course of your lifetime. Especially in running or lateral movements the barefoot is king. It was made to adjust to changes in conditions and terrain. The most common ankle injury is a sprain or roll. Normally this happens when the shoe is planted in the ground but is unable to communicate a sudden change in the terrain and the shoes goes left ankle goes right. These issues don't plague the barefoot runner. Why? Because without knowing it your body does what it is made to do without having to think about it; i.e. proprioception. You can't help but keep the foot under the hip, lean forward, and make ball of foot contact when barefoot. You might say that with modern advances, cement, blacktop, etc... that going barefoot is dangerous. But I defy you to try it. What you'll notice is a buildup of the pads of the feet toughening them dramatically over time thus making it easier to move all on any type of surface. Start slow with sandals or converse all stars and then make the jump. If you are in the gym kick off your shoes and try a couple sets without and see how it feels. Revel in the freedom of not having worry about sweaty socks and shoes. Kick off the shoes and let those puppies breathe!
