Bone is a complex material that contributes to the structural support for muscles, and connective tissue. It provides a safety barrier for our vital organs and stores calcium, which is fundamental for bone density. Much like muscle tissue, bones are constantly being broken down and built back up, this process is known as remodeling. ‘Osteoclasts’ refers to the bone cells that are instructed to break down and remove bone, versus ‘Osteoblasts’ that deposit new bone. We obviously want to promote the latter. The process of bone remodeling is influenced by a range of different things, one of which includes physical stress, more specifically weight bearing activity.
Take away point: ‘Osteoblasts’ deposit new bone! Exercise to promote osteoblasts.
There is so much research out there now in support of the potential benefits of resistance training in correlation to bone density. Resistance training is one such physical activity that is increasingly being advocated as a means of retaining and even possibly increasing bone mineral density. The stresses that come with load bearing activity help to activate the ‘osteoblasts’ and favour bone deposition. Implementing weight bearing activity goes beyond just improving bone density, other benefits may include increased strength as well as an improved ability to perform activities of daily living. For many, incorporating physical stress with daily exercise often results in additional advantages such as a heightened sense of independence to carry out everyday functional tasks (like lifting and carrying your grocery bags, luggage, and the grip strength to open a tightly-sealed jar) and of course decreased risk of injury and falls.
Take away point: Specifically load bearing activity favours bone deposition – lift weights to maintain your independence and avoid injury (when mishaps happen, like tripping or falling).
Lifting weights is protective! By loading the body with weight beyond your own, you’re forcing muscle tissue and bone to break down and then overcompensate in the rebuilding process! This is known as Supercompensation. This is the adaptive rebound above the baseline where the body basically rebounds from the lowest point of greatest fatigue.
Take away point: Supercompensation is the training period AFTER which the trained parameter has a greater performance capacity than it did initially.
Training can generally be broken down into four stages:
- Before Training (Initial Fitness)
- Training
- Recovery
- Supercompensation
Refer to the image below.
A training regime begins with a base level of fitness and strength – you’re starting point to monitor future progress against – ‘Before Training’.
Upon entering the ‘Training’ phase, fitness and strength will decrease. This is intended and to be expected. It sounds counterproductive but it’s a crucial part in the process of building both lean muscle mass and improving bone density. During a weight training session, provided the load is sufficient, you’re placing muscle tissue and bone under a significant amount of stress.This is a healthy kind of stress that’s required to reap strength and fitness gains. All the progress you gain actually happens during your recovery! This is precisely why it’s so important to prioritise things like nutrition and sleep.
The following phase of ‘Recovery’ is essential to progression whereby levels of fitness and strength will increase back to where you initially began. Stay on top of your nutrition and establish a healthy sleep regime to optimise your body’s ability to recover and progress!
Now, since the human body is such an adaptable organism, it then feels the need to adapt to a higher level of strength and fitness in anticipation of your next training session. Subsequently, this increase goes beyond the ‘Before Training’ base levels of strength and fitness, and enters a period of ‘Supercompensation’. The body OVERcompensates during the process of repair in preparation for your next session! At this stage strength and fitness exceeds its initial levels, hereby resulting in a stronger and fitter you, and the cycle continues…
Muscles, connective tissue and bone go through this supercompensation cycle. Muscle tissue tends to work on a 48-hour cycle, tendons and ligaments closer to a 72-hour cycle, and lastly bone, around a 96-hour cycle. Connective tissue and bone take considerably longer to adapt compared to muscle tissue BUT ALL require excess loading to be preserved and get stronger.
Take away point: Weight training strengthens bone, muscles, tendons, ligaments and collagen by repairing itself beyond initial levels of strength and fitness, ultimately preventing degeneration.
When appropriately progressed, there are safe and enormously beneficial ways for people to improve their bone and musculoskeletal health that consequently will assist in everyday living. Resistance training yields increases in bone mineral density, lean mass and muscle strength. There is virtually no one that would NOT benefit from load bearing activity, provided gradual progression is considered. Anyone and everyone should be encouraged to either start or continue with some kind of weight bearing activity due to the myriad of health gains that come from it!
Get to lifting! If you’re unsure, seek help from a well educated fitness professional.
By Louise McCallum