Why should you care about bone health?
When you’re young, concepts like osteoporosis and bone health can seem remote. Like arterial health and muscle mass, think about saving up for the future. Building bone health when you are young is like putting a lot of money in your savings account for a time when you’ll have less cash. As we age, our bone density decreases and the risk of mortality from falls increases at a crazy rate. For example, the biggest cause of accidental deaths below the age of 65 is accidental overdose. As we age, deaths due to falls increases, until by age 85 and over it’s the dominant cause of accidental death. See the table below for a visual representation.
In those who have falls, the older you are, the higher your risk of mortality from a hip fracture. Multiple studies have shown this in many ways. This study found that Older adults have a 5- to 8-fold increased risk for all-cause mortality during the first 3 months after a hip fracture.
We should all pay attention to bone health. And it’s never too early to think about it. Let’s start by defining the terms.
Source CDC database https://www.cdc.gov/nchs/data-visualization/mortality-leading-causes/index.htm
What are osteoporosis and osteopenia?
Osteopenia and osteoporosis are points on a spectrum of bone loss. Osteopenia is the start of loss of bone mass – meaning that you have less than optimal bone mineralization (calcium and phosphorus) and osteoporosis is a greater loss of bone mass.
In osteoporosis the bone becomes porous and more likely to fracture.
What are some things that increase your risk for osteoporosis?
1. Gender. Your chances of developing osteoporosis are greater if you are a woman.
2. Age. The older you are, the greater your risk of osteoporosis.
3. Body size. Small, thin-boned women are at greater risk.
4. Ethnicity. Caucasian and Asian women are at highest risk.
5. Family history.
Looking at the risk factor the stereotype of the “thin, middle-aged white woman” who practices yoga fits factors 1-4.
What can you do about it? And does yoga protect your bones?
One obvious answer is to consume adequate calcium and vitamin D. The active form of Vitamin D (D3) helps to maintain bone by increasing calcium absorption in the intestines. Lack of vitamin D is associated with the bone disease rickets, where the bones lack mineralization. Consuming adequate calcium and vitamin D is important, but not sufficient to guarantee healthy bones. Bone mass typically peaks by age 35. As we go beyond 35, it’s important to keep the bones strong both through diet and activity levels. In order to really get strong bones, you need to stress your bones. Until we invent full-contact yoga, it's unlikely to do a lot for bone health.
Stress Your Bones
Our bones function to keep us upright and provide a scaffolding for our muscles. When we stress our bones, they become stronger and better equipped to withstand stress. You’ve probably heard that weight bearing activities are good for bone health. Activities like resistance training and weight lifting put stress on our bones. Muscles attach to our bones through tendons. When we pull on bones through tendons we give them a work out. When you put a load on muscles you make the bones stronger as well. The big question is which activities stress our bones most.
This study compared bone mineral density from forms of competitive exercise. The highest BMD was resulted from Mixed Marshal Arts (MMA) and Football. I’m not advocating that you should start playing football. But the study shows that the shear force put on bones helps to increase their strength. This doesn’t account for the other injuries and hazards of football and MMA. But you need to stress your bones in order to make them stronger. Activities like swimming, running and walking have little impact on bone health.
Rather than MMA and football, the sweet spot for muscle stress and bone health is resistance training. Track and field tended to be higher BMD than distance running – likely from power and jumping. So running, swimming, and walking don’t tend to do a lot for BMD. To make walking more of a bone workout try walking with a weight – follow Michael Easter for more on rucking (a form of walking with weight). Jumping rope has also shown improvements in BMD in several studies.
Image source: https://www.journalofexerciseandnutrition.com/index.php/JEN/article/view/10/7
How much resistance training?
It's important to start slow and build up over time. While some yoga can function of resistance training, you probably need to use weights to really get your muscles to put stress on your bones. For example, holding handstand for repeated reps would be a good way to build deltoid and upper back strength. And some studies have shown modest improvements in bone mineral density of the spine and femur from yoga. This is because holding your weight on your arms is a much bigger load than we normally carry. But you have to do several reps to really stress those muscles. A more efficient approach is to gradually add weights and strength training. The goal of yoga isn't necessarily to build strength, it's effects are multi-system and impact our physiology in a number of ways. But building big muscles isn't yoga's biggest strength:)
Yoga does help to decrease our fall risk as we age. Because in yoga we work on balance, yoga does have benefit to mortality and aging. See this meta-analsysis for more information.
Start with two strength sessions per week and build up to 3-4 20 minute sessions. Try to work all the body areas, especially the arms, torso and thighs.
If you want to build muscle, it’s important to get the right kind of protein in the right doses.
But this topic deserves its own post.
Stay tuned.