Miles to Go: The Path to a Healthier Heart

Cardiorespiratory fitness (CRF) is a critical component of overall health, directly influencing longevity, health span, and sports performance. Understanding and improving CRF can significantly reduce the risk of various chronic diseases, improve life expectancy, and enhance quality of life. Central to this concept is VO2 max, a key indicator of cardiorespiratory health.

VO2 max, or maximal oxygen uptake, refers to the maximum amount of oxygen the body can utilize during intense exercise. It is often considered the gold standard for measuring cardiorespiratory fitness because it reflects the efficiency of the heart, lungs, and muscles in oxygen delivery and utilization. A higher VO2 max is associated with better endurance and overall cardiovascular health.

VO2 max has been linked to a lower risk of premature death from several causes, including cancer and cardiovascular disease. A pivotal 2018 study published in JAMA by Mandsager, Harb, and Cremer found that individuals with higher VO2 max levels had a significantly lower risk of all-cause mortality and cancer related deaths. This is partly due to the strong connection between cardiorespiratory fitness and reduced inflammation, improved vascular health, and better metabolic function.

Research also shows the importance of VO2 max in aging well. Experts have emphasized that improving VO2 max through regular aerobic exercise can extend health span (the period of life spent in good health) by reducing the risk of diseases such as diabetes, hypertension, and heart disease. Furthermore, increased VO2 max has been associated with a longer lifespan, as individuals with higher fitness levels are more resilient to age-related declines in function.

Aging naturally leads to a decline in VO2 max, which contributes to diminished physical capacity and poor overall health. However, VO2 max can be improved at any age, delaying the negative effects of aging. A 2023 review in Cardiovascular Medicine determined that interventions to improve cardiorespiratory fitness, such as structured exercise, are among the most effective strategies to slow aging and prevent frailty.

VO2 max is also associated with improved cognitive function and lower rates of dementia. By maintaining or increasing VO2 max through regular aerobic exercise, older adults can significantly improve their cognitive health and reduce their risk of neurodegenerative diseases.

The following are two methods that are effective for Vo2 max training: 

1. Norwegian 4x4 Interval Training

A popular and highly effective training technique for improving VO2 max is the Norwegian 4x4 Protocol. This method consists of four intense four-minute intervals at 90 to 95 percent of your maximum heart rate, each followed by a three-minute recovery period. If you are just starting out, begin with twenty to thirty second intervals and build. Of course, prior to starting a new exercise routine, please consult with your physician.

2. Zone 2 Training

Another effective approach for improving VO2 max is Zone 2 training, which involves exercising at an intensity that corresponds to 60 to 70 percent of your maximum heart rate. This moderate-intensity exercise, performed consistently, has been shown to increase mitochondrial density, improve fat oxidation, and boost VO2 max over time. Using the Rate of Perceived Exertion scale can be helpful to ensure you are in Zone 2. If you can talk during exercise but it feels uncomfortable, you are in the correct zone.

For endurance athletes, such as triathletes, runners, and cyclists, VO2 max is a critical factor in determining performance. By improving VO2 max, athletes can enhance their aerobic capacity, allowing them to sustain higher intensities for longer periods without fatigue. Interval training, like the Norwegian 4x4 protocol, is particularly beneficial for endurance athletes seeking to boost their VO2 max.

Cyclists, for example, can use VO2 max data to tailor their training to increase power output at submaximal intensities. Similarly, triathletes can use VO2 max testing to identify weaknesses in their aerobic capacity and structure training to improve efficiency across multiple disciplines.

VO2 max can be accurately measured in a laboratory using equipment like the Cardio Coach system by Korr Medical Technologies. This device measures the amount of oxygen consumed during exercise, providing real-time data on VO2 max. Athletes and individuals can use these measurements to monitor progress and adjust their training protocols accordingly. This assessment is offered in the sports performance gym at Intermountain Healthcare. 

Cardiorespiratory fitness, as measured by VO2 max, is a powerful predictor of health, longevity, and sports performance. Research consistently shows that improving VO2 max can reduce the risk of death from cardiovascular diseases, cancer, and other chronic conditions while also improving overall quality of life and extending health span. Whether you're an endurance athlete seeking to boost performance or an individual looking to improve overall health, incorporating VO2 max-focused training like Norwegian 4x4 intervals and Zone 2 training into your routine is a proven strategy to improve fitness and longevity.

If you would like to learn more about VO2 max testing or other methods to measure your cardiorespiratory fitness, contact Intermountain Sports Performance at 435-251-3733 or email [email protected].