4 Reasons why Cardio is necessary for every Athlete’s Heart Health!

Looked upon awkwardly by many, done briefly at the end of each workout, and attached to many myths. Let me introduce – Cardio.

Many think strength training is sufficient, and they avoid cardio training. To a certain degree, that’s totally fine, and in these words lies truth – do what you love and do not waste time on other things. Nonetheless, cardio is necessary for your overall heart health, because it offers unique benefits in the way it challenges your body. These kinds of input can hardly be induced by strength training. Plus, cardio is a huge part of what we as humans were made for from early on.

So for us, strength and skill-focused athletes, it’s always a fine line between not doing cardio or overdoing cardio and impeding our process. Moreover, cardio can even supplement your strength gains and help you recover. But most importantly, it strongly helps you to avoid dying from heart rhythm disorders as you get older. In fact, cardio is one of the best interventions everyone can do for no cost besides nutrition – this kind of prehab works better than any medication afterwards ever will.

Alright, I’ll take my moral high-priest robe off now and stop preaching to start teaching.

What is Endurance?

Before going into the benefits, let’s quickly define what our final goal is – build endurance. By building endurance, we will also by definition provoke the changes that come with it, like:

• Muscular hypertrophy of the heart, especially your left ventricle
• Improved heart stroke volume, meaning better efficiency and capacity per beat
• Mitochondrial Respiration, meaning improved intracellular, biochemistry and processes
• Changes in Capillary Density, construction of new and fine blood vessels
• Efficiency of movement

All of those will only be triggered in minority by conventional strength training, but very intensely by the different types of endurance training lied out down below.¹ The next question you might ask, and I am glad you did so; is; what the heck is endurance? Think quickly about it before proceeding – I always thought it was the ability of your breath and heart to further maintain its function. But as we see it’s less about your heart and breath than one might think at first.

When you look at definitions² cardio is defined:

…as the ability to withstand a stressor physically, as well as mentally, saying that this stressor will inevitably win the battle and crush you.

4 Benefits of Cardio Training

Cardio is necessary for your Heart, Mind and Body

The stress you create takes its toll on many processes and parts of your body. Despite challenging your legs and other parts, depending on which cardio activity you perform, it taxes your heart.
The goal of every kind of cardio training is to raise your pulse and blood pressure, for a longer period of time. This way, your heart muscle gets used to pumping huge amounts of blood through your body reliably. Plus, your whole cardiovascular system gets taxed and therefore stronger.³

But not only do your muscles, heart, and passive structures have to work hard to maintain power output – it’s also hugely about your mental toughness. Per definition. Just look at the guys running ultras. 135 miles in Death Valley? Running onto Mont Blanc and down again? Ultraman? – there is no way one goes through that without intensive suffering. I am always amazeballed by these guys. That’s truly a superhuman feat of the human spirit.

Good Heart Health = Happy Pension

The number one disease which likely will kill us both when you look at statistics is nowadays cardiovascular disease by far. Cancer comes second with half the amount of deaths caused, followed by lung diseases on the bronze plateau. Far off are violent death causes, with suicides aceing this statistic.⁴

So – let’s try to avoid that cause and gain a few years to die by some stupid, yet funny other ideas. What’s more important, in my eyes than overall years, is the quality of these. And that’s where a strong heart comes into play – giving your old age years, a living soul.

Although life unfolds in mysterious ways and this is an immensely complex topic, improving the chances to die by heart disease drastically and still being able to function later on well is definitely worth the shot. Nonetheless, keep in mind that cardio training is only one part of the puzzle and others like sleep, stress management, fulfilment, and foremost nutrition also have a word in your fate.⁵

Get quickly back to Action with Cardio

Not only for training is cardio great, but after you’ve used to it, cardio can also improve your recovery and help you to get fit again for ruthless strength work. Important for doing so is really keeping the intensity low.

The idea behind all of this is really simple – getting more blood into your tissues. And more blood equals more building blocks, more oxygen, faster metabolism. All of that good stuff needed for your body to recover. Simple as that.

Cardio and Strength Training are a good match

Cardio improves your recovery but also benefits your strength directly. Yet at the same time, cardio also opposes strength training directly. It all depends on the extent and intensity. So what paradoxical mysteries am I talking about?

In their extremes, cardio mainly uses other mechanisms than strength and because of the SAID principle, these get enforced the most. While Cardio training errs more on the AMPK side of things, strength training stimulates mTor. These two biochemical pathways are involved in things like anabolism & catabolism, growth & energy conservation, fed & fasted states, and often acts as counterparts to each other. Therefore, the stimulation of one will inhibit the other. One might ask, is that a reason to banish cardio for strength athletes? At first, it makes sense, yet I think the positives outcompete the negatives. Plus, this thought is too simplistic – it doesn’t take into account many factors like volume, intensity, ratios, and the like.

I think a bit of cardio, done with intent, supplements your strength training beneficially, and that is exactly what the literature shows. The biggest benefit is that a strong cardiovascular system will help you recover quickly – directly. Plus, you won’t get out of breath any more so easily and recover quicker in between your sets. Your body also learns to use oxygen better and lung function improves. Plus, cardio can be an awesome Segway into things like breathwork and nasal breathing training.

How do I combine Cardio and Strength Training?

Have a clear Goal in Mind

First – be clear about what you want. If you want to do a cardio cycle for a few months or run your first 10k that’s awesome! But then you need to train for it specifically and not go too hard on the strength work.

It functions the same the other way. As already said – some cardio is important for everyone and can’t be replaced by burpees, but if you want to get stronger train for that and not run every morning. You only have a certain amount of recovery capacities and unless you are a professional athlete, there is little sense in running every day, plus hitting it hard at the skill and strength work. Even for them, the SAID principle is valid, and no gymnast will run a 10k every day.

Program your Cardio Sessions well

To combine both well you should take a close look at your current workout schedule:

• How often do you train per day and for how long?
• Do you train in the mornings or in the evening?
• What is it you train for?

All these answers will influence your cardio sessions. I would suggest doing 1-3 cardio sessions separated clearly from your strength training. For example, run on rest days, or if there are days when you want to do both runs in the mornings and train in the evenings or vice versa. The planning is completely up to you, just make sure there is a break of 6h in between your sessions, and you avoid going for cardio directly after your strength work. Plus, many like to hit the complex stuff first thing in the day and program skill before strength work, strength before endurance work.

A busy program could look like that:

Start slowly combining Cardio and Strength Training

If you’re new to cardio start slow. Start with one session a week and get your body used to this new stimulus and build up its capacities safely. The last thing you want is to overdo it and tear down the efficiency within your strength training.

Especially when starting to run, it is an unknown movement for many with high complexity. It took me almost 4 years to relearn and kinda master – what helped me was the stupidly not-so-slow transition to barefoot and natural running.

So find an activity you like and go for it once a week for 4-6 weeks. Try to avoid HIT and focus on steady state cardio when starting out. Build the habit, as well as the capacities, and then expand from there. Later on, you can try out intervals, HIIT and stuff, but they will never replace the steady state method – they’re two different entities, as we next will discover!

How do different Cardio Methods compare?

Continuous Endurance Training

Continuous Endurance Training aka the Steady State Method, is the most common form of cardio:

• You begin to run and keep running until your desired time or mileage is done.
• The important factor here is it’s generally low-intensity and the continuous work your body has to perform
• Instead of running, rowing, swimming, and cycling are other common steady state activities.

In fact, you can further divide this method into GA1 and G2. Both differ from each other by their intensity, which gets measured with the help of your heart rate. While the former should be around 40-50% of your maximum heart rate, the latter should be around 50-70%.

What both do is to train your heart to be reliable, to continuously perform, and to pump blood through it. To train both kinds of endurance effectively and not get into strength-endurance aim for a time of continuous stress of 14+ minutes without any breaks. For combining it with strength training as your main enterprise, try to stay below 20-30min per session to avoid excessive cortisol release.

Aerobic High Intensity Interval Training

Aerobic HIIT flies a bit under the radar and gets overshadowed by the next guy we look at, aerobic HIIT. So what is the difference?

• Medium-long, sub-maximum effort bouts of a certain movement – e.g. runs or swims
• Followed by a period of rest or light movement like walking
• The goal is to train your heart in various ways depending on how hard you push each bout of work.

To train aerobic HIIT capacities, you want to choose a traditional cardio activity like running, swimming, or biking. Perform each bout for 2-4min and have a break of 1-3x that time. Commonly used is a 1:1 ratio meaning for example for minutes of running followed by 4 minutes of walking or rest. Another common form, without the need to look at a clock, would be to run a mile and then walk a mile. Repeat these for 3-7 repetitions in total.

Depending on how hard each bout will be and how high your heart rate will go this kind of training has the possibility to yield many benefits ranging from muscular gains of your heart, metabolic changes, and neurologic adaptations. Plus, aerobic HIIT is even a great alternative to get beginners off the endless seeming grind of steady state methods.

Anaerobic High Intensity Interval Training

In the last years, HIIT aka Intervals underwent a real hype. They were so famous because you could do much more work in a shorter period of time – the spirit of our modern era. What characterizes hit is:

• Short near-maximum effort burst of a certain movement – e.g. burpees, sprints, jumps
• Followed by a brief, but overall longer timeframe of recovery. Important to note here is that the recovery phase still is a low-intesity movement – there is no complete rest.
• The goal is to train your heart to adjust quickly and recover while under stress.

To train this kind of endurance, aim for short, taxing activities like sprints, swims, and bike sprints. Perform them for 10-30s, and have a break of 1-3x that time. Repeat for 3-12 repetitions in total.
It is important to note that High Intensity Interval Training is no replacement for the basic Steady State Method, as both train different kinds of endurance. While the previous relies on steady, low-intensity stress to keep your heart working, the latter changes between high-stress burst and low-intensity recovery periods, which teaches your heart to quickly adjust. Therefore, both complement each other by provoking different mechanisms of compensation. Nonetheless, they supplement each other well and your general being as a human.⁶

Interval Method vs. Steady State

As briefly noted, both are part of the puzzle, but I wouldn’t solely stick to one. All of them promote different mechanisms of adaptation that are worth pursuing.

There are many different kinds of endurance, as there are kinds of flexibility and strength. None of both can replace the other but influence it. The concept of free gains also applies here. ⁷:

• Think of this like explosive strength and maximal strength – being strong in one benefits the other definitely, but it doesn’t replace dedicated work.
• Another example would be active and passive flexibility – having a huge passive range allows you to build an overall bigger range, but does not automatically strengthen this range.

Fasted vs. Non-Fasted

Another hugely discussed topic nowadays around training in general, but especially cardio, is the effectiveness of fasted vs. non-fasted exercise. I myself am a huge fan of training fasted, although the science looks unclear on its effects for now. I personally think of strong benefits, yet the consensus is mixed.⁸

In my opinion, learning to function solely on fatty acids or even ketones is very worth it. While the effects on weight-loss might be minor, it is by far not all there is. The more subtle adaptations within your metabolism might be well worth it. Plus, having nothing in your stomach feels, at least for me, simply good while training and running on fats promotes a very clear head in general. See what works for you and how your body responds. That’s the most important!

Your Cheatsheet to combine Cardio and Strength Training

• How?
  What activity excites you or do you want to master?
  Cycling and swinning are two great activities to master for all beginners, overweight individuals, and simply those who love them. Running is in my opinion the most natural and beneficial way to train, but also the most complex. I’m sure you’ll find something that’s fun for you!
• What?
  Program cycles of 4-6 weeks and stick to one cardio method (Steady State, Aerobic & Anaerobic HIIT). Start with the minimal amount of repetitions and work your way slowly up. After 4-6 weeks, choose another one to keep your body’s systems constantly adapting, and you interested. Nothing is more boring than constant steady state.
• When?
  Clearly divide cardio and strength training
  Run in the mornings, evenings or on rest days and plan well. This way, a reasonable amount of cardio done without strong motivation to excel every time won’t affect your primary passion.
• How often?
  Start slowly and be observant
  Starting with 1 session a week is totally fine. In the beginning, it is more about getting your body used to cardio and getting the habit down. Later on, you can build up your sessions to the recommended 2-3 per week.
• But watch out:
  You have to focus something
  You will never be top in everything – the myth of the all-rounder is a lie. At least after a certain level of capacities. If you want to get stronger – keep your focus on there, if you want to run a marathon excel in that area. But don’t try to stick to both extremes at the same time. Unless you are a genetic freak of nature, the 1 in 1.000.000 there is no way your body can recover this amount of stress, unless you’re used to it from child age.

1. To be clear. They happen, but to a lesser degree. Your heart will be taxed and therefore experience some growth also when lifting weights, yet the input is vastly different from deadlifting a 100kg for 5r, then running consistently for 20min. The same goes for biochemical pathways that differ majorly (AMPK <-> mTOR), as well as capillary density and the efficiency your heart works at. The SAID principle in action, right?
2. https://en.wikipedia.org/wiki/Endurance
3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6172294/
4. https://ourworldindata.org/causes-of-death
5. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1884359/
6. https://www.unm.edu/~lkravitz/Article%20folder/HIITvsCardio.html
7. https://www.health.harvard.edu/exercise-and-fitness/interval-training-for-a-stronger-heart
8. https://jissn.biomedcentral.com/articles/10.1186/s12970-014-0054-7