Stress, Recovery, Adaption
Training is based on the process of applying physical stress, recovering from that stress, and thereby adapting to the stress such that life may continue under the conditions that include the applied stress. The human body is remarkably efficient and will attempt to remain in a state of homeostasis. In a survival situation, we had to constantly be able to adapt and as a consequence our bodies also learned to be very efficient at conserving and maintaining energy. Therefore it is all about Stress, Recovery, Adaption. In general with good health we utilize about 91% of the energy in our food. In comparison, the efficiency of a car’s internal combustion engine is approximately 12-30% in gas usage. We have adapted to survive and if we had not, we would not be here today.
Depending on how much physical stress is provided, we either adapt or accrue an injury. For beginners in good health starting strength training, the margin of error is larger and adaptation usually occurs quickly (usually 48 to 72 hours), because they are largely underdeveloped. For intermediate lifters their recovery can take longer since the level of stress is closer to their physical potential and they often benefit from a wider variety of exercises than novices. When it comes to advanced lifters the margin of error is very narrow because their body has already adapted close to their maximum potential and small advancements can take months due to longer recovery periods. The good news is that our bodies also can become more efficient at recovery and adaptation, however we still need rest days (a recovery period).
Training disrupts a body’s equilibrium to an appropriate degree. After recovery, performance ability will exceed the pre-stress level. Physical stress is the trigger. Recovery is the rest period where the body rebuilds. Adaption is when our body is now stronger than what it was before training began, such that it is now prepared to handle increased levels of physical stress. If we do not have a rest period after an increased physical stress (working out every day at the same level of physical activity) then our body has a decreased period in which to recover, repair and adapt. That is when injuries can accrue.
As we grow older our recovery period could be longer and our adaptations slower than when we were in our early 20’s. On average we lose 5 lbs of lean mass (the mass of all organs except body fat, including bones, muscles, blood, skin, etc) per decade between the ages of 25 and 65. Bone and muscle loss is metabolically active and decreased levels help to account for a slowed down metabolism. Strength training can help to mitigate some of this loss with physical stress that causes our body to adapt and build more muscle and bone tissue. Nutrition of course is also another important factor, but if we leave our nutritional intake the same, just strength training alone should make a difference to our body as we age. We may not shrink in size due to not addressing our nutritional needs, but we may notice instead that we feel stronger, can accomplish things easier, etc.
Carefully prescribed specific strength training can benefit our running if we are also a runner (the stronger we are the easier it will be to do whatever our activity is that we love to do). However not all strength training in my opinion is equal. Using gym equipment to lift something is not equal to learning how to lift free weights. There is a reason that gyms have so many lifting machines, and that is because their trainers do not have to teach their clients how to safely lift a free weight (such as a kettlebell or barbell) and therefore there is a decreased risk of injury to the gym’s clients. Utilizing free weights is more akin to real life. In real life we are probably not going to use a piece of equipment to pick something off the floor in our house. The other great boon of free weights, is that more muscles are utilized at a bigger range of motion. In other words, though it takes more time to learn how to lift free weights safely, they provide a much bigger bang for the buck.
Strength training therefore is very similar to our lives in general. Just being alive we have at some point, experienced some stress. If we are open to growth, we eventually learn to recover and adapt. The trick is knowing when to ask for help and who we can lean on in difficult and challenging situations. Some stress is good. Too much stress without a chance to recover is bad for us both emotionally and physically.