It began with the discovery of a male skeleton on the island of Tinian, which lies 1, miles 2,km east of the Philippines in the Pacific Ocean, in The remains were dated to the 16th or 17th Century, and they were positively gigantic. The finding slotted in nicely with local legends of enormous ancient rulers, who had been capable of truly heroic physical feats.
As other graves were discovered, it became clear that the first skeleton was no anomaly; in fact as well as fiction, Tinian and the surrounding islands had been home to a race of extraordinarily brawny men. But where had they got their strength from?
In the case of Taga, he was buried amongst 12 imposing carved stone pillars, which would originally have supported his house.
Meanwhile, a closer inspection of his bones and others has revealed that they have similar features to those from the Tonga archipelago in the South Pacific, where people do a lot of stone working and building with massive rocks. The largest such house on the island had pillars that were 16ft 5m high and weighed nearly 13 tonnes each — about as much as two full-grown African elephants.
This was no mysterious race of muscular giants; the men achieved their powerful builds by sheer hard work. If, in the future, the same technique were used to piece together how people lived in , the scientists would find characteristic changes in our skeletons that reflect our modern lifestyles. The time we spend on our smartphones appears to be changing the shape of our skulls Credit: Alamy.
Until recently, this type of growth was thought to be extremely rare. In , when the spike was first investigated, the renowned French scientist Paul Broca complained that it even had a name at all. Feeling that something might be up, Shahar decided to investigate. Together with his colleague, he analysed over a thousand X-rays of skulls from people ranging from 18 to 86 years old. What the scientists found was striking.
The spike was far more prevalent than they had expected, and also a lot more common in the youngest age group: one in four people aged had the growth. Why could this be? Peak bone mass PBM is one of the most significant predictors of osteoporosis , a condition in which bones become brittle and weak.
As we age and our hormones start to shift, the rate of bone breakdown tends to be faster than the rate of bone growth and building. Estrogen is one such hormone that plays a role in bone health and is produced in lower amounts as women age. Estrogen inhibits bone breakdown and may stimulate bone formation.
When estrogen levels decrease, bone loss can occur as a result. Too much breakdown with not enough rebuilding can result in osteoporosis, and puts you at a higher risk for bone fractures. Since we know that bone break down occurs at a faster rate later in life, it is key to build up bone mass early in life. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services.
Bone is densely packed with flexible fibers termed collagen , hardened by calcium and phosphorus. They are built to withstand great stress from activities like walking, running and jumping.
Bone is a living tissue that constantly renews itself. In your early 20s, the density of minerals in your bones peaks. Hip and knee joints may begin to lose cartilage degenerative changes. The finger joints lose cartilage and the bones thicken slightly.
Finger joint changes, most often bony swelling called osteophytes, are more common in women. These changes may be inherited. Lean body mass decreases. This decrease is partly caused by a loss of muscle tissue atrophy. The speed and amount of muscle changes seem to be caused by genes. Muscle changes often begin in the 20s in men and in the 40s in women.
Lipofuscin an age-related pigment and fat are deposited in muscle tissue. The muscle fibers shrink. Muscle tissue is replaced more slowly. Lost muscle tissue may be replaced with a tough fibrous tissue. This is most noticeable in the hands, which may look thin and bony. Muscles are less toned and less able to contract because of changes in the muscle tissue and normal aging changes in the nervous system.
Muscles may become rigid with age and may lose tone, even with regular exercise. Bones become more brittle and may break more easily. Overall height decreases, mainly because the trunk and spine shorten. Breakdown of the joints may lead to inflammation, pain, stiffness, and deformity.
Joint changes affect almost all older people. These changes range from minor stiffness to severe arthritis. The posture may become more stooped bent. The knees and hips may become more flexed. The neck may tilt, and the shoulders may narrow while the pelvis becomes wider. Movement slows and may become limited.
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