Diet and bone status in amenorrheic runners

Area of Science:

• Sports Medicine
• Endocrinology
• Bone Health

Background:

• Female athletes may experience menstrual irregularities like amenorrhea.
• Amenorrhea is a known risk factor for reduced bone mineral density.
• The interplay of diet, exercise, and hormonal status in bone health requires further investigation.

Purpose of the Study:

• To investigate the relationship between diet, exercise, and amenorrhea with bone mineral status in trained young women.
• To compare bone mineral density and hormonal profiles between amenorrheic and normally menstruating athletes.
• To assess dietary intake and eating behaviors in relation to menstrual status and bone health.

Main Methods:

• Cross-sectional study comparing amenorrheic and eumenorrheic trained female runners.
• Bone mineral density assessment of the lumbar spine using DEXA scans.
• Measurement of circulating estradiol levels.
• Analysis of 3-day dietary records for energy, calcium, and protein intake.
• Assessment of body composition and maximal aerobic power.

Main Results:

• Amenorrheic runners exhibited significantly lower lumbar spine bone mineral density and estradiol levels compared to eumenorrheic runners.
• No significant differences were observed in body composition, maximal aerobic power, or weekly training volume between groups.
• Amenorrheic women reported significantly lower daily energy intake but similar calcium intake.
• Protein intake was below the US Recommended Dietary Allowance in a majority of amenorrheic women (82%) versus 35% of eumenorrheic women.
• Abnormal eating behaviors are suggested as a potential factor in amenorrhea development.

Conclusions:

• Weight-bearing exercise combined with low energy intake and amenorrhea negatively impacts bone mass accretion in young trained women.
• Low energy availability and inadequate protein intake are critical factors to consider in the bone health of amenorrheic athletes.
• Early identification and intervention for abnormal eating behaviors may be crucial for preventing bone loss in athletes with amenorrhea.