Cardio Controversy

Contrary to popular belief the fitness industry does not hate cardio. Although it’s gotten a bad rap in recent years, cardiovascular exercise is essential for improving overall health.

Cardiovascular training has been a topic of conversation in the fitness world for decades. It has gone from the fad to bad over the years, but what is it really? Cardiovascular training is an extremely crucial part of a healthy fitness routine. It strengthens the heart muscle allowing it to pump blood more efficiently throughout the body, reducing the risk of heart disease. It helps lower blood pressure also reducing strain on the heart and arteries. Beyond heart health is improves insulin sensitivity, helping regulate blood sugar levels, which prevents type 2 diabetes. It also aids in weight loss, boosts mood and cognitive function, improve lung capacity, strengthens the immune systems, improves joint flexibility, increases bone density, and improves overall quality of life. Cardiovascular exercise is one of the keys to a longer lifespan yet in recent years it has been pegged as something that hinders you from reaching your physical goals. Why?

It's not that cardio is inherently bad for you, but with diet culture and the obsession with being skinny, it has been overused leading to a number of negative consequences especially amongst young women. Cardiovascular exercise in excess is taxing on the body and puts a lot of stress on your joints, hormones, mental health, etc. Overtraining with cardio can lead to persistent fatigue, insomnia, frequent illness, gut issues, mood disturbances, and hormonal imbalances. Many women who overuse cardio can lose their menstrual cycles and get stuck in a vicious cycle that wreaks havoc on their hormones and metabolism. Excessive cardio can elevate cortisol levels in the body, leading to muscle mass loss, increase body fat, and weakened immune function. High levels of cardio can cause a drop in testosterone, affecting muscles growth and overall metabolism. The high volume of repetitive movements involved in cardio can also lead to stress fractures, tendinitis, and other overuse injuries. After I ran the New York Marathon, I had amazing endurance but experienced severe IT band syndrome, which ultimately did more to harm my overall health that the positive improvements seen from all that running.

With all that being said, I don’t want to discourage anyone from doing cardio because ultimately you need it, in moderation, and it is better to do more cardio than none at all, in my opinion. Incorporating adequate rest days and varying our workout intensity to prevent overtraining is key in establishing a healthy cardiovascular exercise routine. I also recommend focusing on weight training as well, especially while doing things like marathon training to help prevent some of those overuse injuries that can take place when you have muscle imbalances or weak joints and are doing excessive cardio. Using cycling, rowing, or swimming as your cardio can also alleviate some of the overtraining issues caused by higher impact cardio like running.

Another important aspect of cardio to understand is that there are 5 different cardiovascular training zones, each that provide a different health benefit. They are defined by the percentage of your maximum heart rate (MHR) and help guide the intensity of workouts. Zones are bucketed as 1-5 ranging from very low intensity such as dynamic warmups to maximum effort (or VO2 max), such as sprints. If you are as deep in the fitness and wellness algorithm on Instagram as I am, you are probably most familiar with Zone 2 cardio.

Zone 2 cardio is a form of aerobic exercise performed at 60-70% of your maximum heart rate. It is characterized by a moderate intensity level where you can maintain a conversation without feeling out of breath. This type of training is often referred to as "base training" because it builds the foundation of aerobic fitness and endurance. Zone 2 improves the body’s ability to switch between using fat and carbs for fuel, in essence training our metabolism to be flexible and reducing insulin resistance. This type of training increases the number and efficiency of our mitochondria, the energy powerhouses of our cells, leading to better energy production and less fatigue. This is also the zone where fat is used as fuel, making it an effective way to train for fat loss while preserving muscle. Common Zone 2 workouts include the viral 3-12-30 treadmill workout which involves walking on a treadmill at 3mph at a 12% incline for 30 minutes. Zone 2 cardio is low intensity, placing less strain on your musculoskeletal system, promoting faster recovery and reducing injury risk. It is also shown to have positive mental health benefits and is associated with lower risk of chronic diseases.

To calculate, you subtract your age from 220 to estimate your maximum heart rate, then calculate 60-70% of this value for your Zone 2 range. Another easy test to see if you are in Zone 2 is being able to hold a conversation comfortably while exercising. It is recommended to perform Zone 2 cardio 3-4x a week for about 45-60 minutes each. Zone 2 is thought to be a cornerstone of a balanced fitness regimen, offering numerous benefits for both physical and mental health while enhancing overall performance and longevity and has changed the narrative once again on cardio. Incorporating sessions from each Zone can help prevent plateauing in your fitness journey and reduce burnout or overtraining. By understanding how to properly perform different types of cardio and building them into your routine helps maximize fitness gains, improve performance, and help you achieve specific goals you may have safely and effectively. Long story short, cardio is a tool for improving overall health and reaching your goals but should be used in moderation.