http://goo.gl/5xZCVA
The researchers invited 34 men over the age of 65 to hop for 2 minutes a day for one year. The men hopped only on one leg, so the other leg could be used for comparison.
Bone mass increased by up to 7% in parts of the exercised hip's outer shell or cortex. The results also showed increases in the density of the layer of spongy bone under the cortex.
These effects were also seen in the thinnest areas of the hip bone - the parts that are most likely to suffer a fracture during a fall.
The findings could help to prevent and manage osteoporosis, a disease that is responsible for more than 8.9 million fractures worldwide every year, resulting in an osteoporotic fracture every 3 seconds, according to the International Osteoporosis Foundation.