Here at the C.H.E.K Institute, an exercise can only be considered functional if it fulfills the following criteria:
- Comparable reflex profile (Righting and Equilibrium reflexes)
When moving across any object, stable (earth) or unstable (surf board), the body uses reflexes to maintain your upright posture. People with brain and spinal cord injuries often have to perform certain exercises to restore these reflex actions. Athletes needing particular reflex responses can use specific exercises to target the reflex profile they need to improve.
- Maintenance of your center of gravity over your own base of support
Whether standing at the sink brushing your teeth (Static postural component), or performing a walking lunge, squat or power clean (Dynamic postural component), failure to maintain your center of gravity over your base of support results in falling and possibly injury.
- Generalized motor program compatibility
The most functional exercises use movements that have a high carryover to work and sport. The best functional exercises have a relative timing profile similar to many other activities. For example, the squat exercise has a very similar relative timing profile to jumping, yet the leg press, knee extension and hamstring curl machine are very different, which is why they do very little if anything to improve vertical jump performance!
- Open/closed chain compatibility
If you push against an object and you can not move it, such as performing a chin-up, the chain (muscles/joints) is closed. When performing a lat pull down you are overcoming the resistance and thus, the chain is open. Because the recruitment of muscles and movements of joints is task specific, your exercise selection must be equally specific to achieve an functional outcome.
- Improves relevant biomotor abilities
Each exercise is composed of "biomotor", or "life-movement," abilities. According to Bompa (8), biomotor abilities are strength, power, endurance, flexibility, coordination, balance, agility and speed. An exercise is most functional when the biomotor profile most closely approximates the ability lacking in the athlete’s body or when it most closely resembles the task being trained for.
- Isolation to integration
Bodybuilding has plagued athletic training and rehabilitation with the urge to "isolate" muscles and make them BIGGER! It should never be forgotten when trying to improve functional performance, the brain only knows movements, not muscles. To achieve optimal results with any isolation exercise, adequate time must be spent training the muscle to contribute to a functional movement pattern.