Nursing research study participant considerations

Nursing Research Study: The effects of calcium and vitamin D supplementation on female, high school cross country runners

Overview of Study Scientific Rationale and Purpose

Stress fractures are small cracks in the shaft of a bone caused by overuse or excessive physical stress. "About sixty-nine percent of stress fractures occur in runners," the rest in recent military recruits ("Stress Fractures," 2006, Mass General Hospital for Children). 21 per cent of female recruits are reported to suffer from this form of injury. ("Calcium, vitamin D may reduce stress fracture risk," 2007, NutraIngredients). "Predisposing factors include running after a period of inactivity, change in the running surface, poor training and inadequate shoes," as well as weakened bones because of inadequate diet or poor bone density ("Stress Fractures," 2006, Mass General Hospital for Children). Frequent dieters may also be at higher risk for stress fractures caused by osteoporosis, regardless of their weight, as the body compensates for the decreased caloric intake by reducing its bone-building functions (DeNoon, 2006).

It is true that weight-bearing exercise is advised to increase bone mass amongst the elderly and amongst dieters. However, if the rate of bone turnover is too high because of heavy exercise, cracks and weakened bones are also the result. "The truth is, simply being an athlete doesn't protect your bones" (Pipenberg 2005: 2). Lifting weights is often recommended as a supplementary exercise to increase bone-building hormones. However, military recruits perform weight-bearing training, so weight lifting alone is not a solution.

But recently, a study presented at 53rd annual Orthopedic Research Society meeting in San Diego suggested that daily supplements of calcium and vitamin D could aid in the prevention of stress fractures. The study was a randomized, double-blind study encompassing 5,201 female U.S. Navy recruits during their eight weeks of basic training. "What really surprised us is that calcium/vitamin D supplements made a significant difference in such a short period of time. Frankly, we were not sure we would see any statistically significant results in only eight weeks," said the lead researcher ("Calcium, vitamin D may reduce stress fracture risk," 2007, NutraIngredients). One group of study participants received a daily supplement of 2,000 Mg of calcium and 800 IU of vitamin D, and the other group received a placebo and at the end of the eight weeks of basic training, 170 women in the placebo group experienced stress fractures; 25 per cent more women than in the calcium/vitamin D supplemented group ("Calcium, vitamin D may reduce stress fracture risk," 2007, NutraIngredients)..

Who is eligible to be in the study; what type of patients will be involved?

But what about the other commonly afflicted population, that of female long-distance runners? This study will examine the same additional calcium/vitamin D supplemental treatment in high school, female, long distance runners. Female cross country runners between the ages of 14-17 years old will be eligible. Although none of the personal data collected on the runners will be shared without the student's consent, the parents and coaches of the runners must give permission for their daughters to be part of the study

Where and when the study will be conducted and the length of commitment

The study will be over the course of the average duration of the cross-country season, which is 14 weeks. Additional testing will be done at a hospital, with transportation costs to be reimbursed for the participants.

What tests or procedures will the study involve? Do they have risks? Will they cause pain or discomfort (physical or mental)?

Miles run, a history of menstruation, and diet will be logged, and use of hormonal contraception (estrogen levels affect bone development). These factors will be used to allocate study groups, to control for variables that can affect bone health. Also, questions about weight history, preseason activity, mileage, cross training (like weight lifting) and running shoes will be asked of study participants during pre-screening questioning and study group allotment. This is because "genetic, hormonal, and nutritional factors play a significant role in the development of stress fractures....Female runners with a history of stress fracture are more likely to have a history of irregular periods or lack of periods. A low body mass index is also a predictor of reduced bone mineral density in adolescents" ("Stress Fractures," 2006, Mass General Hospital for Children).

To gain a sense of the relative the bone density of the participants a DEXA bone scan pre -- and post-season will be required. (Pipenberg, 2005: 1). Athletes will be screened and questioned weekly regarding pain, performance, and to see if they exhibit other common symptoms of stress fractures.

Anticipated benefits and risks of taking part in the study

Low bone density and stress fractures, combined with irregular menstruation have long been the bane of long-distance runners, especially females. "The teenage years are the most important ones for the accumulation of peak bone mass, which starts to decline after menopause. Therefore, lack of good bone health during adolescence will increase the risk of stress fractures in the near-term and drastically impair bone health later in life (What is the female athletic triad?" 2006, Female Athletic Triad Coalition).

Who will have access to the study information, and what is the plan for protecting the information?

All information will be kept strictly confidential between the researchers and students, unless the student asks that information be released to her parents and/or coaches. If the student's eating or exercise habits appear to be dangerous to her health, however, she may be released from the study.