Lets say the table is long enough to seat 20 women each side. One entire side will suffer an osteoporosis related fracture. Half of the women over 50 will experience such fractures. Had the table been for men over 50, five of them would have been destined for an osteoporosis related fracture. Consuming enough calcium combined with regular weight bearing exercise is vital during these years.
Regular exercise maintains bone mass.
Walking is the simplest exercise, but running, biking and swimming work too. Bearing weight on your body, plus movement across the planet, does retain more bone mass than non weight bearing exercise. However, because the amount of muscle mass affects bone mass, swimming, weight training and other non-impact exercises are also very effective in decreasing risk from osteoporosis. Exercise will help to preserve your present bone mass, while giving a nudge to increase bone mass. The younger you start exercising regularly, the more bone mass you will retain.