Facts and fables about exercise

1. ‘Jumping rope helps prevent osteoporosis’

27 percent think: not true

It’s true. Bee osteoporosis the bones lose ‘bone mass’ (calcium, collagen and other proteins), causing the structure to deteriorate. As a result, they become brittle and break more easily. Exercise has a beneficial effect on bone mass loss. When pressure is applied to the bone, the cells receive a signal to make new bone.

Sports in which you carry your own weight are the most effective for this: running, tennis, brisk walking, as well as dancing and skating. Cycling and rowing are much less effective. Swimming does little for the bones, because the water carries the body. The heavier and faster you put stress on your bones, the more new bone is created. Especially short-term exercises with a high frequency therefore help. For example, three minutes of intensive jumping rope four times a day is better than walking for half an hour for bone formation. For those who already have osteoporosis: exercise certainly makes sense for them too.

2: ‘Exercise reduces the risk of breast or colon cancer’

42 percent think: not true

It’s still true. Exercise reduces the risk of overweight. And those who are overweight are more likely to develop various types of cancer. Not only for breast and colon cancer, but also for uterine, esophageal, pancreatic and kidney cancer and probably gallbladder cancer. For breast and colorectal cancer, the association with overweight has been the most researched. Belly fat in particular seems to be the culprit.

Exercise also appears to reduce the risk of breast and colon cancer for other reasons. Female sex hormones play an important role in the development of breast cancer. And exercise influences the hormone level in the blood. Women who are regularly physically active are about 20 to 40 percent less likely to develop breast cancer than women who do not or hardly exercise. Every hour of extra exercise per week reduces the risk of breast cancer by 3 to 8 percent. You have to maintain this over a longer period of time.

In addition, people with an active lifestyle are estimated to be about 40 percent less likely to colon cancer. This is probably because exercise moves food through the gut faster. As a result, harmful substances from the diet come into contact with the inside of the intestine for less time. This reduces the risk of damage, which means that cancer can develop less quickly.

Researchers think that insufficient exercise, combined with a healthy diet and obesity, is responsible for about 5 to 15 percent of all cancer cases. Even if you only start exercising at a later age, you reduce the risk of cancer.

3: ‘An active lifestyle reduces the medication in type 2 diabetes’

8 percent think: not true

Yet it is so. Bee type 2 diabetes the body is not able to regulate the level of blood sugar properly, causing it to become too high. The hormone insulin plays an important role in this. This brings sugar from the blood to the muscles, among other things. In type 2 diabetes, the body produces less insulin or becomes less sensitive to it. Exercise makes the muscles more sensitive to this hormone, so that less of it is needed to get sugars to the muscles. That is why (many) diabetic patients can manage with fewer medicines by regularly exercising vigorously.

Exercise also has other positive effects for people with type 2 diabetes, says Jan-Willem van Dijk, sports scientist and researcher at Maastricht University. “We have shown that exercising for 45 minutes a day lowers blood sugar spikes after a meal by 30 to 40 percent. These peaks in particular increase the risk of developing cardiovascular disease.

People with type 2 diabetes should therefore either make a long-term effort of at least an hour every other day, or a shorter exercise of at least half an hour every day. To lower blood sugar levels, strength training (which increases muscle mass) is just as effective as endurance training, such as running or cycling.

4: ‘With muscle soreness it is better to rest’

18 percent think: true

Moving slowly actually helps muscle strain, because this improves the blood circulation and thus the recovery of the muscles. If you move little, the muscle pain lasts longer. Ordinary muscle pain, the nagging pain that occurs when you strain your muscles in an unusual way, usually goes away on its own within a few days. Try to keep moving regularly without overloading your muscles.

Muscle pain can also be caused by an infection, such as the flu. Exercising with the flu is not wise, because the flu virus not only affects the normal muscles, but also the heart. After all, it also consists of muscle tissue. Exercising with a fever can cause (dangerous) cardiac arrhythmias. However, walking around quietly is better than staying in bed all day.

With the collaboration of Marijke Hopman-Rock, professor of physical activity and health in the elderly (at TNO and Vumc). This Plus study was made possible in part by A.Vogel.