Bone loss and aging are inseparable: “The skeleton is a systemically regulated mass of mineralized material that is born, grows, reaches a more or less high peak, and then declines faster or slower as to develop a correspondingly high or low fracture risk”(Ferretti et al. 2003). Musculoskeletal aging—declining bone and muscle mass, increasing joint pain and stiffness, and decreasing physical mobility—is a normal part of aging. However, how rapidly or slowly bone mass declines depends on different factors. While genetic abnormalities account for 70% of the variance in skeletal strength (Rizzoli 2014), other factors—like hormones, nutrition, physical activity and toxins—play crucial roles in developing bone and losing it.
Understanding bone loss starts with distinguishing between the two basic diagnoses: osteopenia (low bone mass) and osteoporosis (advanced loss of bone tissue). Then, the smart thing to do is learn about risk factors and preventive measures.
Osteopenia vs. Osteoporosis
More clients may come to you with a diagnosis of osteopenia than with the better-known osteoporosis. Osteopenia points to low bone mass when overall bone mineral density hasn’t fallen far enough to cause serious concern. It’s critical to note that an osteopenia diagnosis does not mean osteoporosis is inevitable. However, if a client mentions this diagnosis, you have an excellent opportunity to explain that physical activity and nutrition are important modifiable factors that can prevent further decline.
We distinguish between osteopenia and osteoporosis via the T-score system, which quantifies BMD (Karaguzel & Holick 2010). Because the T-score measures bone loss, it is expressed as a negative number. A T-score between -1
and -2.5 is defined as osteopenia, while a T-score below -2.5 is defined as osteoporosis.
There are two types of osteoporosis, both characterized by weakened bone and increased risk for fracture: primary (bone loss through aging) and secondary (caused by a variety of diseases, medications and toxic agents). We will focus only on primary osteoporosis since it is the more common type and also the type that fitness professionals can help clients with through physical activity and nutrition.
Osteoporosis is often called the “silent disease” because it’s usually not diagnosed until after a fracture (Porter et al. 2016). Indeed, nearly 80% of older adults who suffer bone breaks have never been tested or treated for osteoporosis (NOF 2016). Following a fracture, the risks of mortality and disability accelerate: 1 in 5 hip fracture patients end up in a nursing home (OSG 2004), and 24% of hip fracture patients over 50 die in the year after the fracture (NOF 2016).
Thus, fitness professionals who help older exercisers confront the risk factors of osteoporosis can be lifesavers.
To read more about the workings of the skeleton and the risks of bone loss, please see "Bone Health: A Primer" in the online IDEA Library or in the June 2018 print issue of IDEA Fitness Journal. If you cannot access the full article and would like to, please contact the IDEA Inspired Service Team at (800) 999-4332, ext. 7.
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