A recent study in The European Heart Journal determined whether peak oxygen targets could lower individuals’ heart attack risk.
VO2 max is also known as maximal oxygen consumption. It is a measure of the volume of oxygen required at an individual’s maximum cardiorespiratory activity. Cardiorespiratory activity is usually an action that requires agility, such as running.
Measuring maximal oxygen consumption
VO2 max is typically measured by having an individual wear a mask and run on a treadmill. The mask detects the amount of oxygen breathed in and the amount of carbon dioxide exhaled. The runner will be pushed to run as fast as they can, for as long as they can and when they reach their maximum level of exhaustion, their VO2 max can be measured.
While cardiovascular disease mortality rates have been decreasing worldwide, it still is one of the primary sources of death, accounting for one-third of all deaths around the globe. Studies have credited at least half of the reduction in mortality from heart disease to advancements in medical technology. If medical technology is advancing, but the prevalence of heart disease is relatively unchanged, one can point to the population not taking preventative measures.
Assessing heart disease risk in relatively healthy participants
Researchers in Norway and Australia believed there were knowledge gaps in what we know about preventing cardiovascular disease. The majority of studies that assess preventative measures against cardiovascular disease usually assess the cardiorespiratory function of middle-aged men. These men are usually at-risk individuals. Thus, the researchers wanted to assess relatively healthy people that do not lie within the bounds of being at extreme risk for cardiovascular disease. The results were published in The European Heart Journal.
The study, known as The Hunt3 Study, assessed 4,527 adults with no previous family history of cardiovascular disease, hypertension, lung disease or lung cancer participated; 51% of participants were women. Blood samples and measurements of height and weight were all collected. Participants also self-reported in a survey regarding their lifestyle behaviours including:
- Alcohol intake
- Smoking habits
- Snuff users
- Physically active
They grouped the individuals into one of the four groups based on their answers. Participants then ran on a treadmill and VO2 max data was gathered. People who were grouped into one group were only compared to others in the same group so that lifestyle behaviours would not skew data. Researchers followed up with participants 10 years later and mainly assessed any instances of death by cardiovascular disease.
Physically active individuals had a 48% lower chance of dying from a heart-related event
Researchers found that among participants who were physically active, 48% lower chance of dying from a cardiac event compared to the group of smokers.
This study showed that there is a negative relationship between VO2 max and cardiovascular disease risk; higher VO2 max decreases one’s susceptibility to mortality from cardiovascular disease. This suggests that by encouraging individuals to measure their VO2 max and work on increasing their VO2peak, they may reduce the risk of heart disease.
Written by Nikki Khoshnood, BHSc Candidate
Reference: Letnes, M. J., Dalen, H., K, Elisabeth., Wisloff, U, V., Nes, M, Bajarne. (2018). Peak oxygen uptake and incident coronary heart disease in a healthy population: the HUNT Fitness Study. European Society of Cardiology.