Cardiorespiratory fitness (CRF) is rapidly becoming one of the most valuable tools in understanding overall health and longevity. For us as fitness professionals, it’s something that should be at the core of our client assessments, right up there with body measurements, strength, and flexibility tests. Why? Because research shows that CRF is a strong predictor of a wide range of health outcomes, including mortality and the risk of developing chronic diseases.
In fact, a comprehensive meta-analysis has revealed that people with higher CRF have significantly lower risks of death from all causes, including heart disease and cancer. This isn’t just about elite athletes—this applies to everyone, including clients who might just be starting their fitness journey. Even small improvements in CRF can lead to substantial health benefits.
Study Overview
This study takes a comprehensive look into how cardiorespiratory fitness (CRF) affects various health outcomes in adults. By reviewing a range of meta-analyses, it pulls together evidence from cohort studies to understand the impact of CRF on things like overall mortality, cardiovascular disease (CVD), cancer, type 2 diabetes, and other chronic conditions.
CRF and Mortality
The research clearly shows that higher levels of CRF are consistently linked to lower rates of death from any cause. In fact, people with the highest levels of CRF saw a staggering 47% to 53% reduction in mortality risk compared to those with the lowest levels. There’s also a noticeable dose-response relationship here. For every 1-metabolic equivalent of task (MET) increase in CRF, the risk of death from all causes dropped by 11% to 17%. CRF didn’t just impact overall mortality; it also lowered the risks of dying from cardiovascular issues and cancer, with the strongest effects seen in those with heart conditions.
CRF and Chronic Disease Risk
When it comes to chronic diseases, CRF plays a protective role. It helps guard against the development of conditions like heart failure, hypertension, type 2 diabetes, and strokes. For instance, a 1-MET increase in CRF can reduce the risk of heart failure by a remarkable 18%, with moderate risk reductions for hypertension and type 2 diabetes as well.
CRF and Clinical Populations
For those already living with chronic diseases—such as heart failure or cancer—higher CRF levels were linked to better survival rates and a reduced risk of disease progression. The evidence shows that those with higher CRF had a much better outlook across a range of chronic diseases, including cardiovascular and pulmonary conditions. This means that improving CRF could significantly improve the prognosis for individuals with these health issues.
Measuring CRF
So, how can you measure CRF in your practice? Thankfully, you don’t need a lab full of equipment to get started. Submaximal fitness tests, such as a step test, treadmill walk test, or cycling protocols, can give a solid estimate of a client’s CRF. These tests allow you to measure your client’s heart rate response to a known level of exertion, helping you to calculate their fitness levels in a practical, everyday setting. Many fitness trackers also offer estimates of CRF based on activity levels and heart rate data, which can be a useful tool for ongoing monitoring.
Once you have this data, you can make more informed decisions about your clients’ training plans. A client with low CRF may benefit from starting with moderate-intensity aerobic exercises like brisk walking or cycling, gradually increasing the intensity over time. The ultimate goal is to help clients increase their CRF by at least one metabolic equivalent of task (MET), which studies show can reduce mortality risks by up to 17%.
CRF and Chronic Conditions
When it comes to working with clients who have chronic conditions, CRF is even more crucial. Many people with conditions like hypertension, diabetes, or heart disease face higher risks of health complications, and improving CRF can significantly reduce those risks.
The same meta-analysis we discussed earlier found that for clients with heart conditions, a higher CRF was associated with a massive 73% reduction in cardiovascular mortality. This means that fitness professionals have a real opportunity to make a difference in our clients’ lives by focusing on improving CRF, especially in clients with chronic health conditions.
But how do you go about this safely? For clients with heart disease or diabetes, it’s important to start slow and monitor their progress carefully. Begin with low-intensity aerobic activities, like walking or swimming, and slowly build up the duration and intensity as their fitness improves. It’s critical to keep an eye on their heart rate and symptoms of overexertion—some clients may need more recovery time, especially if they’re dealing with the fatigue that often accompanies chronic conditions.
For clients with hypertension, regular aerobic exercise can help lower blood pressure, but it’s essential to avoid sudden spikes in intensity. Focus on steady, moderate-intensity exercises like walking or cycling. Over time, as their fitness improves, they’ll not only lower their risk of cardiovascular events but also gain more energy, which will improve their overall quality of life.
Maximising Client Cardiorespiratory Fitness
Improving CRF isn’t just about managing chronic conditions or reducing mortality risks—it’s also about helping your clients lead longer, healthier lives. And the great news is that even small improvements in CRF can have huge benefits.
The study we mentioned earlier highlighted a clear dose-response relationship: for every one MET increase in CRF, clients can see a 11-17% reduction in the risk of all-cause mortality. This means that as a fitness professional, you have the tools to make a substantial impact on your clients’ longevity.
To maximise CRF, it’s all about incorporating regular aerobic exercise into your clients’ routines. Depending on their fitness level, this could range from walking or light jogging to more intense activities like cycling or running. The goal is to keep clients consistently improving their aerobic capacity.
You can track these improvements by keeping an eye on their METs—many fitness devices will calculate this for you based on heart rate and exertion levels. For those without access to this technology, simply gauging improvements in how far or how fast a client can walk, run, or cycle within a set timeframe can be just as effective. For clients who enjoy variety, try incorporating interval training or circuit workouts to keep things fun while still improving their CRF.
Final Throughts
Cardiorespiratory fitness is a powerful predictor of health, and it’s a tool every fitness professional should be using to help their clients achieve better outcomes. By incorporating simple fitness tests into your practice, you can assess and track CRF levels, making it easier to personalise exercise programmes that not only improve fitness but also reduce the risk of chronic conditions and improve longevity. Whether you’re helping clients with heart disease, diabetes, or simply looking to enhance their overall health, focusing on CRF can make a real difference.
We have a unique opportunity to be on the frontline of health promotion by ensuring that CRF is not overlooked in favour of more traditional fitness assessments. By implementing strategies to improve CRF in all clients, from beginners to those with chronic conditions, we can help them live longer, healthier, and more active lives.
Reference
Lang JJ, Prince SA, Merucci K, et al Cardiorespiratory fitness is a strong and consistent predictor of morbidity and mortality among adults: an overview of meta-analyses representing over 20.9 million observations from 199 unique cohort studies. British Journal of Sports Medicine 2024. Click here to review the full research article
Your Fitness Future Starts with TRAINFINESS
Ready to launch your career as a personal trainer? With TRAINFITNESS, you’ll gain expert knowledge in key areas that set you apart in the industry. Our comprehensive courses offer in-depth guidance on conducting sub-maximal fitness tests—essential for accurately assessing your clients’ cardiorespiratory fitness. You’ll also learn how to design effective cardiovascular programmes using top CV equipment and create engaging circuit classes that keep clients motivated. In fact, studies show that improving cardiorespiratory fitness can reduce mortality risk by up to 17%, making your role as a trainer more vital than ever. Start your journey with TRAINFITNESS and become the expert your clients need.
Gym Instructor & Personal Trainer Course – Distance Study, In-Person & Live-Virtual
