RED-S: Accidental Under Fueling and the Male Cyclist

RED-S or relative energy deficiency in sport (RED-S) while not a new phenomenon, is still not always easy to diagnose, especially among male cyclists.

Low energy availability (LEA) basically means a mismatch between calories burned and calories consumed. LEA causes adverse health and performance outcomes including poor bone health and higher risk of bone stress injuries including fractures in both female and male athletes.

Originally called the Female Athlete Triad, for a long-time research focused just on the effects of energy deficiency in female athletes. Today, there is a better understanding of how it affects the male athlete as well, but athletes and their doctors do not always have it on their radar.

Cyclists are a particularly high-risk group for RED-S because they are not aware they are under fueling, and for them the signs of poor bone health are not as obvious given that cycling is a non-weight-bearing sport. Often, they don’t know there is a problem until they experience a traumatic fracture.

A Cycling Weekly survey of 868 riders from earlier this year found that one in five amateur riders are under fueling, putting them at risk for RED-S. And 30% of female and 15% of male respondents reported symptoms of RED-S. That increased to 40 and 36%, respectively, in semi-professionals.

A British cyclist, Doug Bentall, recently wrote about his experience with RED-S in “RED_S: not just a female phenomenon” for the British Journal of Sports Medicine.

Bentall was a runner when he was in school but was forced to give it up after a knee injury at university. Afterwards he took up cycling for leisure, and rode for fun through most of his 30s and 40s. Then at 48 he started working with a cycle trainer so he could pursue it more competitively.

During training, he noticed that he was losing weight but wasn’t really concerned at first, explaining that he wasn’t being vigilant about the nutritional needs of being a competitive cyclist. It wasn’t until he turned 50 and was training for his first duathlon that he became concerned about his health.

He wrote, “At the end of the year, I qualified for the European Age Group Duathlon in Spain in April 2017. I entered a local cross-country event and I won the 50 years+ race, but afterwards, I had difficulty walking. In my opinion, I thought I had just pulled a hamstring as that was what my symptoms felt like. I took some painkillers and ran the Masters’ event the next week, but the problem was still there. With the European Age Group Duathlon only a month away. I stopped running completely and stuck to the bike.”