Every time you move—cross the road, lift luggage, exercise or dash up the stairs— you are engaged in purposeful movement of the body. All these movements are a result of forces developed in your muscles, which move body parts in conjunction with one or more of the lever systems of the skeleton. For instance, if you wish to run from point A to B, then you would begin to use muscles and ligaments along bony levers to create movement. It is important to note that to make movement possible, muscles do not act directly to exert force. They act by pulling against the bones that rotate about joints to generate these forces of movement. Strong, effective and sustainable movement depends not only on muscles, but also on the strength of the bones.
The 200-odd bones in our body make up two parts of the skeletal system, namely the axial skeleton, comprising the skull, vertebral column, ribs and sternum or breast bones; and the appendicular skeleton, which includes bones of the shoulder and pelvic girdles, arms and legs. It is a relatively light, yet immensely strong and stable structure. So much so that the leverage and support this structure provides can ensure stability and movement for an entire lifespan—approximately 80 years or so. Provided, of course, that a person follows a healthy diet and workout regime.
Food for thought
Nutrition and exercise play a major role in keeping our bones healthy. Here are some diet tips to build bone strength:
■ Bone health is synonymous with calcium. Dairy and dairy products are the single most important food group for adequate calcium intake. Adults between ages 19-50, need 1,000mg of calcium per day, while those above 51 need 1,200mg. According to the National Institute of Nutrition, Hyderabad, a cup of cow’s milk (236ml) contains approximately 283mg of calcium. A cup of yogurt has 300mg, half a cup of cooked broccoli, 93mg, 30g of cheese, 100mg, and 2 tablespoons of almonds contain approximately 80mg. These also make for a great snack.
■ After calcium, phosphorous is the second most abundant nutrient in the body. Phosphorous supports bone mineralization, and about 85% of it is found combined with calcium in the form of hydroxipatite crystals in bones and teeth. Again, broccoli, yogurt, cottage cheese, eggs, fish and poultry are significant sources of this mineral.
■ Magnesium, a micronutrient found in several foods such as nuts (almonds), whole grains (brown rice), dark green vegetables (spinach and methi) and dark chocolate, also plays a vital role in bone mineralization.
■Vitamin D and K are unique nutrients because they are obtained from non-food sources and are synthesized by the body. Vitamin D is synthesized with the help of sunlight and vitamin K from bacteria in the gastrointestinal tract. Vitamin D raises the blood concentrations of other bone-making minerals, which ensures a continuous supply of calcium and phosphorous to the bones. Vitamin K, on the other hand, synthesizes bone proteins to regulate calcium levels in the blood. Vitamin D can be synthesized in the body with fortified milk and dairy products, egg yolks and fatty fish like Indian salmon and mackerel. Bacterial synthesis of vitamin K in the digestive tract is aided by eating liver, leafy greens, and vegetables from the cabbage family.
Lead an active life
Physical activity is critical for bone health. Sitting for long periods weakens not just the unused muscles and bones, but also the intricate connections between muscle forces and skeletal lever systems and joints that make dynamic and stable movement possible. In addition, if the person also consumes junk food, then the body’s calcium absorption ability is compromised, which in turn reduces bone mineral density and affects bone health. Over time, such people can develop either type 1 osteoporosis, characterized by rapid loss of bone density, increased risk of spontaneous fracture ( even sneezing could fracture a rib), excruciating pain, and reduced mobility, or type 2 osteoporosis, where the bone loss is gradual. People with weak bone health are also susceptible to osteopenia, a less severe form of bone loss.
To guard against this, lead an active lifestyle or join a gym. Weight or resistance training is an effective means to build bone density as the “load” that this form of training puts on the bones and their supporting muscles, tendons and ligaments, counteracts bone tissue losses. Resistance training, especially exercises that load the axial skeleton, like weighted squats, lunges, deadlifts and overhead presses, are great for building bone health.
This article was first published on LiveMint.com