Q My shin bones usually feel really sensitive to touch for hours after running. It doesn’t feel like shin splints and hurts only when I press on the bone. I’m a female runner and I’ve been running for about 10 years. I’m currently running 6-10 kilometres four to five times a week and walking on the other days. I don’t do as much cross training as I would like to because I have a 15-month-old and an extremely busy schedule. I do however teach and practice yoga. I’m also still breast-feeding and just recently returned to a normal menstrual cycle. In the past when I was running much more I would often go through periods of amenorrhoea [the absence of a menstural period in a woman of reproductive age], usually for a few months. Could both of these factors cause weak bones? I’m 172cm and weigh 65kg and have always had thicker calves and ankles. I also went to a local running shoe store that helped me pick out proper shoes for my foot and running type. Any help I could get would be much appreciated. – MELISSA
A Bone is a very dynamic tissue and turns over regularly. If that turnover involves stress changes or micro fractures in the shin bone, you could experience the pain you are describing. Bone is the storage area for calcium and calcium balance in the body is regulated by a complex set of hormones and vitamin D. Pregnancy puts a stress on your calcium supply as the developing baby has needs for bone growth that tap the mother’s reserve. Bone deposition has an estrogen component and both pregnancy and breast feeding can disturb the balance. Your hormone cycle has likely normalised recently with the return of your menses.
I would suggest you take a calcium supplement if you are not getting 1500mg or more mg of calcium in your diet daily and a vitamin D supplement of 1000-2000 units daily (especially if you live in the southern half of the country) at least until you are a few months past breast feeding. Your previous episodes of amenorrhoea may have left you with a lower bone density and could be experiencing the latent effects of exercise-related amenorrhoea combined with your recent pregnancy and breast-feeding. This is why it is so important for teens and young women to eat well and have adequate energy stores to support bone deposition during the bone building years before age 30.
You might also consider cutting your mileage in half for a few weeks and then slowly rebuilding to your current level. Breast feeding is still stressing your calcium store. You could use the extra time to do some core strengthening, as a stronger core may take some of the pressure off your shins. – WILLIAM O. ROBERTS