Today we’re going to talk about cardio. Although my focus with clients is lifting weights, cardio should be a staple of everyone’s weekly routine. So let’s discuss!
To meet the health guidelines, we should be doing at least 150 minutes of moderate, or 75 minutes of vigorous, cardio per week (or a mixture of the two). This can be achieved through a huge number of activities: walking, running, group exercise classes, swimming, boxing, playing sports, and so on. Cardio is essential for heart & lung health (hence ‘cardiovascular’ exercise) and, in most cases, I’ll just advise you to find a form of exercise you enjoy that lifts your heart rate above resting for a prolonged duration (30, 45, 60 mins etc). This is absolutely fine and a great way to ensure you actually do your cardio exercise consistently!
However, if you want specific adaptations to your cardiovascular system… then we need to go a little deeper!
Energy systems & heart rate zones
Firstly, to be ‘doing cardio’, you need to be working at at least 60% of your heart rate max (HRM). This is known as ‘Zone 2 cardio; where your heart rate is between 60-70% of your heart rate max. Working in this zone trains your aerobic energy system. Anything below this percentage is considered a resting state.
Now, without getting too complicated… your body has THREE energy systems, which are all working together – but the one being predominantly used and trained, depends on the type of exercise you are doing:
1. Aerobic (up to 70% HRM) – This is the energy system used when exercise lasts many hours – eg. a long endurance run (it’s also the energy system we predominantly sit in, ie. when we are resting).
2. Anaerobic: Lactic Acid system (70-85% HRM) – this is the system used for high intensity exercise lasting 10 seconds-3 minutes (eg. a HIIT class)
3. Anaerobic: Creatine Phosphate system (85-100% HRM) – this is the most intense one! Used for maximal effort exercise lasting 0-10 secs (eg. sprinting)
So what energy system you train, depends on your goal! If you want to improve your cardiovascular endurance, maybe for a long run, to improve stamina in day to day activities, or to improve your recovery between lifts (as recovery = aerobic!), you should be training the aerobic energy system aka. doing “Zone 2 Cardio”. This is what I’m going to focus on here, to keep things simple – and because it’s the logical place to start. See aerobic training as the foundation of your house. You have to build this first.
How do know you’re doing Zone 2 cardio and working your aerobic energy system?
First, you need to calculate your heart rate max (HRM). Do this with the following sum: 220- your age, then find 60-70% of that number. I’ll give myself as an example:
220-37 (my age) = 183 (my heart rate max)
0.6 x 183 = 109 (60% of my heart rate max)
0.7 x 183 = 128 (70% of my heart rate max)
So in order to improve my aerobic fitness, when I am doing cardio, I need to keep my heart rate between 109-128 beats per minute (BPM).
Note: This type of training will probably feel very slow, and very boring, and like nothing is happening. This is totally normal and is how it should feel in most cases. We are so used to thinking cardio is only ‘working’ if it absolutely destroys us, we can’t talk and we are dripping in sweat. Zone 2 cardio… probably won’t do any of that. But it WILL build and improve your aerobic energy system, which is responsible for giving sustained, long-term energy, and helping you recover faster with less breathlessness during other types of exercise (eg. lifting weights) AND during activities of daily living (eg. carrying shopping up stairs).
This from the website ‘Strength Matters’ explains it rather well:
“People spend the majority of their time in the aerobic system. Think about it. Walking, moving, being at work, just living life. A stronger, more robust aerobic system carries over to everything you do in life.
However, here’s the problem. Most people in today’s society have completely lost the ability to perform basic aerobic sustainable functions. Walking is a great example of this.
Biologically, humans are set up to “go long” or sustain work for extended periods of time. However, this is no longer the case in society.
Modern society is allowing us to become lazy. We don’t have to walk as far. We take elevators instead of stairs. We drive short distances to get to our destinations. We sit more than we stand.” So I hope this shows you the importance of aerobic training, and how to do it. If improving aerobic fitness is a goal of yours, use the above formula to calculate your heart rate max and 60-70% of that number. Then choose your cardio (walking, cycling, etc.) and monitor your heart rate to ensure you stay within those two numbers. Start with 10 minutes. As the weeks go on, gradually increase that amount. This is how you train your aerobic system.
Conni
Conni Arnold Fitness 