Weight-bearing exercise for strong bones
Weight-bearing exercise involves any movement in which you have to support your body weight. These can be done with your bodyweight alone or with resistance. This type of exercise helps build bone (when you’re younger) and helps protect against bone loss (when you’re older).
Any type of physical activity will benefit your overall health, but weight-bearing exercises are best if you have low bone density. When you bear weight through your bones, it stimulates the bones to produce more cells, improving bone mass and, therefore, bone strength.
Some examples of weight-bearing activities include:
- Jumping rope
- Tai chi
- Climbing stairs
- Low impact aerobics
Why you need both types
It is worth noting that weight-bearing exercise alone is not enough for healthy bones. It is vital to have an exercise program that incorporates both weight-bearing exercises and strength training to optimize the bone-building effect. Weight-bearing activities stimulate bone growth by loading the bones against gravity. More robust muscles protect bones and joints.
A 2015 meta-analysis involving post-menopausal women found that combining resistance training with weight-bearing exercises such as walking is more effective at increasing bone mineral density (a measure of bone strength and health) than only performing resistance training (Zhao, 2015). Another study found that walking alone was not enough to preserve bone strength when compared to those who participated in both walking and resistance training (Martyn-St James, 2008).
So how much resistance should be used? In short, you should be adding weight to increase the usual demand on your body so that you are loading the body more than you would normally experience while performing daily activities. The exact amount can be different for each person. By using exercise bands or weights, muscles and bones are loaded and challenged in a way that will stimulate growth.
The greatest bone stimulating effect from resistance training is when load is increased slowly over time. So if you are just beginning to perform resistance exercises, find a resistance that will allow you to perform 2 sets of 8-12 repetitions with good form but that leaves you feeling challenged. After 3 months of using this resistance, you should be able to gradually increase the weight or band being used.
Are heavier weights better for your bones?
Weight-bearing exercise can include aerobic activities that involve moving your own body weight. Aerobic exercises are considered to be low or high-impact exercises. High-impact aerobic exercises, such as running, jogging, and jumping, puts more force through your bones and are not for everyone. Those with advanced osteoporosis, a history of falls or low bone mineral density should avoid this type of exercise to prevent the risk of fractures.
When it comes to strength-training exercises, the resistance used does not have to be extremely heavy to elicit an effect. Resistance can be added to a movement through resistance bands, weight machines, or free weights, such as dumbbells. Some resistance exercises, like squats, don't even need added weight to be considered strength training. For example, squats can be varied and more challenging by simply changing the pace (squat down for 3, stand up for 1).
Many weight-bearing exercises are also strength-training exercises. When adding weight to movements, more doesn’t always mean better. As long as you are adding some resistance or challenge, you will be eliciting a muscle strength-building and bone-building effect.
How to get the best results
To get the best bone-building results from your workouts over time, you're going to want to try progressive loading, which we'll describe in a moment. But as a general rule, consider the following:
- Varying workouts to include lifting weights, aerobic activity, and balance exercises to combat or prevent osteoporosis and lower fracture risk.
- Making sure that your body has the resources it needs to build new bones and muscles. So be sure to eat a diet with plenty of calcium and vitamin D.
- Meeting with a physical therapist who understands osteoporosis and its possible progression. A physical therapist can assess your specific needs and deficits and ensure you are moving forward with the best course of exercise for your body.
Progressive loading is a principle of strength training that involves gradually increasing the demands placed on the body over time. Think of it as gradually making your weights heavier. If you were to lift the same amount of weight for a year, there would be no change in your strength. Progressive loading is the dynamic process that is necessary to continuously challenge your body so that you keep adapting and building more strength. The National Strength and Conditioning Association (NSCA) guidelines recommend progressive loading as an effective method for developing strength (NSCA, 2012).
The principle of progressive loading involves gradually increasing your weight, reps, or sets over time to continue challenging the muscles and causing your body to adapt by becoming stronger. The goal is to stimulate the muscles to adapt and get stronger while avoiding injury or overtraining. Here's how progressive loading works in practice:
- Start with a baseline: Establish your baseline strength by performing a 1-rep max (1RM) or another strength assessment. Your 1RM is the maximum amount of weight you can lift for only 1 repetition for a given exercise. If you tried a second rep, you wouldn't be able to do it confidently. This will help you determine the starting point for your training program. But keep in mind finding your 1RM can have risks if you're not sure what it might be -- it's always best to start with light weights and only go up to an amount of weight that feels challenging but safe.
- Set goals: Determine what you want to achieve with your strength training, such as increasing your 1RM, or improving strength to improve bone health. Your doctor or physical therapist may be able to help you figure this out.
- Choose your exercises: Select the exercises that target the muscles you want to develop. This can include multi-joint exercises like squats and lunges, or isolated exercises such as bicep curls.
- Choose the right load: Choose a weight that is challenging but allows you to complete the desired number of reps with good form.
- Increase the load: Gradually increase the weight over time as you become stronger. The NSCA recommends increasing the weight by 2-10% for upper body exercises and 5-10% for lower body exercises. You'll want to check your 1RM every few weeks to see if it has changed. When it feels easier to use that initial weight, try increasing it slightly and working with this new amount.
- Vary the reps and sets: As you increase the weight, you may need to adjust the number of reps and sets you perform to avoid overtraining. The NSCA recommends performing 2-6 sets of 1-6 reps for strength development, but if you are lifting less than your 1RM it's ok to do 10 reps.
- Monitor your progress: Keep track of your progress by recording the weight, reps, and sets you perform for each exercise. This will help you determine when it's time to increase the weight or adjust your training program.
Overall, progressive loading is an effective way to develop strength and avoid plateauing in your training. By gradually increasing the weight over time, you can continue to challenge your muscles and stimulate adaptation. However, it's important to use proper form and avoid overtraining to prevent injury and promote long-term progress. If you haven't spent a lot of time training over the last several weeks or months, or if you are hesitant to lift more than a certain amount for any number of reasons, listen to your body. The 1RM strategy isn't for everyone. It's ok to start with lighter weights to get comfortable with an exercise before making the exercise more challenging with resistance.
Finding the right exercise dose for you
If this all seems like a little too much information to swallow, here's the simpler strategy to follow:
The Bone Health and Osteoporosis Foundation recommends a combination of performing weight-bearing exercises (30 minutes a day on most days of the week), muscle-strengthening exercises (2-3 days per week), and balance exercises (every day). Wellen's personalized home fitness bone health program includes all of the above and will keep you on track with your bone strengthening goals. Calcium gets a lot of credit for being responsible for building strong bones. However, exercise—especially the right kind—is just as crucial for bone health. In order to elicit a bone-building response, you must exercise with force that exceeds the demands of normal daily activities. This can be done in a variety of ways and with different types of equipment, such as dumbbells or exercise bands. It's up to you to determine what amount of weight feels challenging but doable, and when you are ready to try the next weight up.