High Impact? Jumping? The science behind the most effective exercises for bone density.

Osteoporosis is a skeletal disorder characterised by compromised bone strength predisposing a person to an increased risk of fracture.

A DEXA derived Bone Mineral Density (BMD) T-score of -2.5 or more constitutes a diagnosis for osteoporosis. A BMD T-score that falls between -1 and -2.5 is classified as osteopenia (low bone bass). Common sites for osteoporotic fractures are the spine, hip, wrist, and arm.

Most osteoporotic fractures occur because of a fall; hence it is important to optimise bone strength and reduce falls risk. Exercise is highly recommended as a modality to help develop bone health. However, not all exercise modalities are recommended for bone health, and below are the recommended options.

The exercise loading must involve movements that are dynamic, induce high bone strains, and be applied rapidly. It is also important to apply short bouts of load that are separated by periods of rest.

Athletes that participate in high or unusual impact weight-bearing sports such as gymnastics, volleyball, basketball, powerlifting, and tennis have superior bone mass to non-athletes or athletes in non-weight bearing sports such as swimming.

However, the most practical ways for people to increase or maintain bone strength would include a combination of strength training and jumping activities. When doing strength training, the resistance would need to be increased progressively for maximal benefits. For example, if an older adult is squatting 4kg in their first week, then, it would be advised for the weight to gradually increase to a higher number by week 8 (I.e. 16kg). This would ensure muscle and bone adaption over time. It is recommended for the person to lift around 80-85% of their maximum weight.

Exercises that focus on increasing balance is also recommended in reducing someone’s risk of falling. Dual-task training is recommended to improve someone’s ability to perform activities in situations where they might be distracted by two tasks. This would also help reduce someone’s falls risks. Examples will include counting backwards from 100 while doing a lifting exercise.

It is also advised for people in their teenage years to maximise their bone mass to delay the development of osteoporosis later in life. The bones are more receptive to exercise in childhood than in older age.

Although impact and muscle strengthening exercises are highly bone stimulating, the person’s level of frailty would need to be considered prior to undertaking an exercise plan. Certain risk factors that include, age, muscle loss, presence of co-morbidities, history of bone fractures, menopause and use of medication would need to be evaluated to determine the level of exercise loading.

An exercise program should also consider individual goals, preferences and interests to heighten exercise adherence and long-term commitment.