Sails & Springs

Boats have sails and humans have springs. The Mesopotamians invented the sailboat in 1300B.C. allowing them to harness the endless resource of the wind to move with greater ease and efficiency. Springs, like sails, also capture energy for the sake of forward movement. The iliotibial tract, or IT band is connective tissue made of collagen that works like a strong rubber band in our leg. The downward force from gravity is transfered into this tissue to be stored as elastic energy for a split second, which helps propel the leg forward with extra lift. Our fascia and tendons are the the sail and gravity is the wind.

We can increase the size of our sails through weight training and exercise. Weight training causes our body to fortify our joints under stress, strengthening the connective tissue. The strengthening of  connective tissue not only makes joints stronger, but allows our muscles to more efficiently transmit force to the skeleton. This means that all our movements become more powerful and efficient. This also means a decrease for chance of injury.

Hydration is important to maintain the elasticity of these tissues. A dry sponge is hard and easy to tear. In contrast, we want our tendons and fascia to be as soft and flexible as a wet, juicy sponge fresh from washing dishes! Microvacuoles are the tiny hoses that deliver water to all areas of our tissues. After long periods of sitting or days of inactivity these small hoses begin to lose their shape, getting small kinks as they collapse from dehydration. Just drinking water won’t open these back up. That’s why soft tissue work with self care tools or massage is vitial for people who spend much of their lives sitting still at work, in the car, and on the couch.

It is important to remember that fascia is very strong and can withstand 2,000 pounds per square inch of pressure. Often at the gym you will hear people talking about working on their IT band with a foam roller because it’s tight after a long run. Is this effective? Think of the IT band as a rope that is being pulled by two sailors on either side of a boat. If you want to stop the tension, don’t try to stretch out the rope, try and get the sailors stop pulling! This means working the large muscles at the top of the IT band. The gluteus maximus and the tensor fasciae latae are the silent work horses of the leg, moving it through flexion and extension. Relieving the tension in these muscles will bring back the bounce in your step, and with all your running rigging ready, let you sail off into the future.

The notion that the IT band acts as a spring to aid in locomotion runs counter to the decades-old belief that its primary function is to stabilize the hip during walking. ‘Unlike many clinicians and anatomists, we use the lens of evolution to think about how humans are adapted not just for walking, but also for running, so we look at the IT band from a totally different perspective,’ [Daniel] Lieberman said. ‘When we looked at the difference between a chimp and a human, we saw this big elastic band, and the immediate idea that leapt out at us was that the IT band looked like another elastic structure, like the Achilles tendon, that might be important in saving energy during locomotion, especially running.’ One part of the IT band stretches as the limb swings backward, Eng explained, storing elastic energy. That stored energy is then released as the leg swings forward during a stride, potentially resulting in energy savings. ‘It’s like recycling energy,’ [Carolyn] Eng said. ‘Replacing muscles with these passive rubber bands makes moving more economical. There are a lot of unique features in human limbs — like long legs and large joints — that are adaptations for bipedal locomotion, and the IT band just stood out as something that could potentially play a role in making running and possibly even walking more economical.’
— Peter Reuell reporting for the Harvard Gazette