Stress Fracture Influences Bone Resorption marker (u-NTX) in Female Long Distance Runners

Abstract

In this study, we aim to clarify the influence based on bone resorption markers at onset of stress fracture. Also, we will clarify the state of the bone resorption markers of female long distance runners who have a history of stress fracture and also ones who routinely practices running long distances. Participants comprised 19 female long distance athletes. The survey period was 2011–2014, and we measured u-NTX as a bone resorption marker at least twice a year, taking the mean±SD of the periodic measured values without stress fracture as the mean value. Measurements were collected sample when stress fractures developed. 132 u-NTX measurements were taken from 19 participants. As a result, the average was 41.03±12.31 nmolBCE/mmolCRE (Q1: 33.15, Q2: 40.55, Q3: 47.95). In six of the 19 participants, u-NTX could be measured following a stress fracture. The mean value of u-NTX for those participants was 40.16±9.10 nmolBCE/mmolCRE, increasing to 64.08±16.07 nmolBCE/mmol CRE with the stress fracture (p<0.01). The findings showed that, in adult female long distance runners, u-NTX values when there was no stress fracture were within the standard value for mean premenopausal women, but increased when the athletes suffered from a stress fracture.

Bone Metabolism, Bone Mineral Content, and Density in Elite Late Teen Female Sprinters

“…The higher values observed in our participants, compared with those of the above studies, was considered to have been affected by repetitive weight bearing from sprinting. These markers evidently increased in individuals with bone injuries, including stress fractures [27]; however, none of the participants in the present study experienced a bone injury at the time of the measurements. In our participants, the bone turnover markers decreased even with continued training and approached the adult premenopausal reference range over the 1-year study period.…”

“…The higher values observed in our participants, compared with those of the above studies, was considered to have been affected by repetitive weight bearing from sprinting. These markers evidently increased in individuals with bone injuries, including stress fractures [27]; however, This document was downloaded for personal use only. Unauthorized distribution is strictly prohibited.…”

Physiological Factors of Female Runners With and Without Stress Fracture Histories: A Pilot Study

“…In a sample of adolescent female cross-country runners, elevated bone markers were associated with a lower body mass index, menstrual irregularities, and lower estradiol and vitamin D levels. 2 In contrast, Fujita et al 14 measured bone resorption (urine N-Tx) twice per year in a small sample of female runners aged 19 to 34 years and found that while N-Tx values were normal during training, they increased when an SF occurred. These findings suggest that N-Tx may be a noninvasive way to identify SFs and monitor healing.…”

Low Energy Availability and Relative Energy Deficiency in Sport: What Coaches Should Know

“…Depending on the duration of their LEA, athletes may also present with altered bone geometry compared to their healthy peers, particularly decreased trabecular area in weight-bearing bones such as the pelvis 38,139,140 . The lower bone density and weakened structure can lead to increased risk of bony stress injuries that in turn can lead to stress fractures, which results from imbalanced bone resorption and bone formation 79,114,145 . Such scenarios are especially problematic for female athletes because they tend to be at higher risk of developing bony stress injuries compared to their male counterparts due to anatomical and hormonal differences [146][147][148][149] .…”

“…estrogen, testosterone) on bone metabolism. In some cases of LEA, particularly those involving intentional restricted caloric intake, athletes may not get sufficient calcium and vitamin D, both of which are essential to generating new bone 85,141,142 As a result, 12–45% of athletes with LEA tend to have lower bone mineral density, between one and two standard deviations below the population average 38,114,139,143,144 . Depending on the duration of their LEA, athletes may also present with altered bone geometry compared to their healthy peers, particularly decreased trabecular area in weight-bearing bones such as the pelvis 38,139,140 .…”