How Run/Walk Intervals Can Improve Back Pain,
I have a 16 1/2 year old daughter who is a cross country and track runner at her high school. Before that she was a Junior Olympic cross country and track athlete. She was an All-American cross country athlete (top 25) and in 8th grade she was 2nd in the nation in the 1500. Her mile time was a 4:58. Unfortunately, she has just been given the news that she has a femoral stress fracture. This is her third stress fracture since she was 13 years old. Her first one was the 4th metatarsal in her left foot then she got one the next summer in her right foot and it was a navicular stress fracture, which required surgery. When she was out injured with the navicular stress fracture I had a bone density test done on her to hopefully get an answer to why she got that injury to avoid it happening again. I was told that since she is a teenager there wasn't baseline numbers to compare hers too. Also I had her blood tested to make sure she wasn't deficient in anything and she seemed fine in all her numbers according to her pediatrician. She started her period in the 8th grade but has never been regular, even when she wasn't training. However, it is my understanding that maybe this might have something to do with it. I am just looking for help with trying to figure out what may be going on and I wanted to find out if you have ever encountered a teenage girl that has experienced similar recurring injuries.
Thank you for your time,
Lisa
Dear Lisa,
Your daughter’s story points to the female athlete triad and the lowest common denominator seems to be energy availability. Your daughter is clearly a talented runner, but will need to solve this puzzle to be successful at the high school, college, and professional level (should she choose to pursue running at the highest levels). I have seen this in some of my patients over the 30+ years of my career. One of the differences I have observed caring for the elite professional runners is the ability of the successful team members to consume the calories needed to support the huge volume and high intensity workouts required for success at the top levels of running and still have the body energy required to support normal menstrual cycles and bone health. The lyrics in current popular music reflect the pressure girls and women feel to stay thin and restrict calorie intake, “I ain’t no size 2” and “run that extra mile, so they like you.” This peer pressure is not lost on runners, and thinness may be a motivator for some young distance runners.
Why Its Important to Avoid Running Through Injury:
- Training volume and intensity that is too high for the bone and muscle strength to support the activity
- Inadequate energy availability to support the bone mineral density needed to tolerate the stress and strain of the training volume
Likely there is a combination or continuum of these underlying problems contributing to the stress fractures in many girls and women. In the teen years, the body grows rapidly and requires increased energy availability and proper nutrition to support the transition to the adult body habitus - this is also when the vast majority of bone calcium is deposited in the bones for bone strength. During these times of rapid growth, the bones grow in length and the muscles “stretch” to lengthen. Changes in the lever arms and body center of mass put unaccustomed stress and strain on the bones and muscles, which could result in stress fracture from uncompensated mechanical forces. Reducing training volume and intensity during these growth spurts, along with an increase in calorie consumption, might reduce the risk of stress fracture. In girls, there is also a change from a more “boyish” figure as a pre-adolescent to the broader hips of a fully developed woman that can change the mechanics of running; another potential mechanical cause of stress fracture. Women athletes have a natural “meter” for adequate calories and that is a regular menstrual cycle (although low body energy is not the only cause of amenorrhea). For most adolescent girls and young women with abnormal periods, the issue boils down to inadequate calories in the diet to support the energy demands of training and body functions.
A femoral stress fracture is a big deal as a completed fracture means a femoral rod or similar hardware is needed to allow the bone to heal. During the time away from running, working on diet and strength to reduce the future stress fracture risk may help her future training. Inadequate energy is not always due to eating disorders and can simply be the result of difficulty ingesting enough calories to support the activity levels.
Thank you for your time here. You might be able to find a primary care sports physician near you through the You can read more about the female athlete triad who could review your daughter's medical evaluation, possibly suggest other evaluation steps, and help you through this problem. Your daughter may also benefit from a few sessions with a sport nutritionist and you can find one in your area here.
Thank you for sharing your story. The female athlete triad is unfortunately common in young female athletes and maybe some mothers or other runners who read this will also be helped. Good luck to your daughter and maybe I will see her on the Team USA Minnesota roster in the future.
Study Says VO2 Max Better Health Marker Than BMI.
Cheers,
Bill
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