A pilot study led by researchers at North Carolina A&T State University has shown a correlation between hypertension and low-energy availability in Black Division I athletes.
While there have been numerous studies on the elevated risk of hypertension and cardiovascular disease on Black people, there have only been two studies focused on Black athletes. The studies, performed in 2009 and 2013, respectively, focused on the correlation between football players and blood pressure, ventricular hypertrophy and cardiovascular disease risk factors. Some of the methods and guidelines used across both studies are outdated.
For Troy Purdom, study lead and assistant professor in North Carolina A&T’s department of kinesiology, the foundation of the study was adhering to updated guidelines which have been in effect for five years.
“We used the revised American Heart Association and American College of Cardiology blood pressure standard,” Purdom said. “The reason why they were revised in 2018 was what they found was considered pre-hypertensive which in the old guidelines used to be just a general warning sign. It turned out in a five-year follow-up there’s a high percentage [chance] that those with pre-hypertension became hypertensive.”
23 athletes studied
To illustrate a link between low-energy availability, nutritional content, and hypertension in Black Division I athletes, Purdom and his associates recruited 23 Division I athletes spanning four sports. Thirteen men and 10 women represented volleyball (five), track and field (nine), football (one) and men’s basketball (eight). The average age of the group was 19 years old. The participants also averaged 5-feet-10, 170 pounds, and 19.2% body fat.
Besides monitoring blood pressure from a cuff, Purdom used an eight-point analysis device to measure body composition and a treadmill stress test to evaluate cardiorespiratory fitness. After the study participants sat for five minutes or more, Purdom measured and evaluated their blood pressure according to the revised guidelines.
Since 2018, the American Heart Association and American College of Cardiology has defined prehypertension as a systolic reading of 120 mmHg or more and/or a diastolic of 80 mmHg. The guidelines also state that Stage I hypertension is considered to be in the 139 mmHg systolic over 89 mmHg diastolic range.
After laboratory evaluations, the athletes completed a food recall interview to access their nutrition. They used the Nutritional Data System method to assess energy intake. The athletes were required to log their daily nutritional intake and include food content, the time of day they ate, and the amount of food consumed for three days. After they logged their intake, a sports dietitian performed a five-step review of the athletes’ food records.
What is low-energy availability?
Low-energy availability is defined as the underconsumption of energy or nutrients to meet activity demands. The lack of calories consumed is likely to accompany nutrient deficiencies. Deficiencies in calcium, vitamin D, iron, and fatty acids are shown to negatively affect cardiovascular health. According to the study, low-energy availability affects cardiovascular health directly through conditions and activities.
A typical day in the life of a student-athlete is rigorous. If an athlete is calorie and nutrient deficient and in a constant state of low-energy availability, the likelihood of cardiovascular damage increases.
Study results: Athletes weren’t eating enough
Of the 23 athletes recruited for the study, 14 were shown to have hypertension. Within the affected group, 87% were found to be calorically and nutrient deficient in micronutrients such as poly-unsaturated fatty acids (-29.6%), omega-3 (-26.0%), iron (-46.0%) and sodium (-14.2%).
According to Purdom, these numbers suggest a perception that the nutritional link between these athletes and hypertension is them not eating healthy. It suggests a breakdown either in the athletes’ responsibility to monitor their diet or an issue with what’s being served during team meals. Surprisingly, the issue isn’t in the quality of food; it’s in the quantity. The data in the study showed that the athletes who did not eat enough were 10 times more likely to have high blood pressure.
“Calories are the fuel that we put in our bodies that helps our bodies run off of energy,” Purdom explains. “So if we don’t eat at adequate energy, we are going to see high blood pressure as a result, so much that we found a moderate relationship among our sample that the less they eat, the higher their blood pressure will get.”
Sean Rayford/AP Photo
The hypertensive athlete’s profile
According to Purdom, “an athlete such as a football lineman carries higher amounts of body fat, which is known to increase the risk of hypertension.”
“In our athlete cohorts, which only included one football player, we found that there was still a very high risk of cardiovascular disease among them,” Purdom said.
Among the four sports profiled, basketball and track and field are the most demanding cardiowise because the athletes in those sports use the most energy. To link this certain group of athletes to hypertension and low energy availability is a shock to most but the study shows a logical explanation for the link.
“The current recommendations for Americans are to eat less and exercise more,” Purdom said. “However with athletes, they’re different. They exercise well beyond the standard guidelines and often they don’t eat enough and that creates some physiological effects that are very negative.”
Solutions
When he learned of the results of the study, North Carolina A&T athletic director Earl Hilton suspected a correlation between the athletes and hypertension, and was happy that the research spotted a correlation.
“I was delighted that we were able to do the research and to establish the connection so that we could take appropriate remedial and preventative measures to assist our student-athletes,” Hilton said.
With a connection in place, Hilton began collaborating with Purdom to evaluate cardiovascular function over time. Hilton provided resources from the athletic department, from recruiting athletes for the studies to purchasing the necessary equipment to conduct the studies.
Currently the university has a job opening for a sports dietitian who has experience working with Black athletes and athletes who have been diagnosed with chronic conditions such as hypertension. The university’s department of athletics is also looking to hire nutritional support staff.
“We hope to create a sports performance enhancement center here on campus,” Hilton said. “We have some spaces we’re looking at that might be identified and converted to that kind of research center. We feel like there is a pretty significant opportunity here to provide data, to provide information that will work to the benefit of our student-athletes, and to provide them with information to be more successful academically and athletically.”
As for the student-athletes, they, according to Hilton, are more aware and proactive in their approach to their health.
“There’s certainly an awareness of nutrition and the impact that it has. Not just their athletic performance, but their academic performance and their sleep. That’s not new to this generation of students,” he said. “Culturally, I think as a society, we’re much more aware of the impact of nutrition, the impact that nutrition has on every facet of our lives, and these student-athletes are no different.”
