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Why aerobic training is so crucial given our current situation

What are high intensity workouts actually doing for our health and is there value in long slow runs?

If I asked you to name the most common cause of disease related deaths in The United States of America, or here in the United Kingdom, what would spring to mind? The most common answer from many would be Cancer.

Now imagine if I told you that, combined, all the conditions that link to Cardiovascular Disease, such as Stroke, Atherosclerosis and more, kill more human beings yearly than every form of Cancer combined?

Considering this, let’s talk about how it is possible to develop cardiovascular disease (CVD).

CVD is most commonly associated with Low Grade Inflammation.

A sedentary lifestyle (or conversely, a highly stressful lifestyle) and poor diet can induce a chronic state of inflammation within the body, which can in turn lead to the development of conditions such as Type 2 Diabetes, Hypertension, Hyperlipidaemia and CVD.

Enter the Autonomic Nervous System (ANS)

The ANS is the regulator of your internal environment. Everything from Blood Pressure to Blood Sugars are very tightly controlled by this system. Regardless of what you’re doing, whether fasting for 7 days straight or performing a bungee jump, your ANS is making sure that absolutely nothing is out of whack.

It also manages production and storage of energy.

Now imagine that you’re at the Zoo, observing the cutesy little Meer cats popping up out of their burrows, constantly on high alert for predators and seemingly unaware that captivity does not bring the inherent dangers of surviving in the wild…  All of a sudden a terrified patron runs past you screaming-

‘The lion! It’s escaped from its cage! ‘

You spin around just in time to be confronted by the sight of a gigantic African mammal, walking casually toward you, licking its lips.

At this point, your survival depends on the body’s ability to produce a massive amount of energy very quickly, necessitating your need to dash for the nearest exit at lightning speed. It is at this very moment that your ANS engages your Sympathetic Nervous System.

The Sympathetic Nervous System

Energy management is regulated via two branches of the ANS.

When being chased by a lion- or even in a non-life threatening situation such as simply having a bad day at work- the Symapathetic Nervous System is primarily in charge. Its functions are as follows-

Increase Heart Rate

Increase Blood Pressure

Release Fat and Sugar into the Blood Stream

Divert Blood to working Muscles

Reduce Appetite

Dilate Pupils

All of the above states put your body into a PRO-INFLAMMATORY STATE.

(Remember how we talked about Inflammation being the pathway to disease?)

On the flipside, we have the Para-Sympathetic Nervous System. Its functions are as follows-

Lower Heart Rate

Lower Blood Pressure

Store Energy

Stimulate Digestion

Increase Appetite

Constrict Pupils

All of the above put your body into a rested or ANTI-INFLAMMATORY STATE

Both systems control Inflammation.

Now, some inflammation can be a good thing. Recovering from the mechanical and metabolic stress of a heavy lifting session requires a degree of inflammation in order to trigger the recovery process. This is acute inflammation and is a transient but beneficial form of stress. However, if we take the typical 9-5 worker with a family life who has an hour to work out at the end of the day and we beat them into the ground for 3-5 sessions a week, all we’re really doing is compounding already potentially high levels of stress.

Exercise of any sort usually comes with a rewarding release of endorphins. These feel good hormones are a natural pain killer and this is why exercise can become addictive. So whilst you’re killing yourself in the gym every night and cranking your sympathetic nervous system all the way up to 11, the post workout high that follows is the biggest reason that you will be right back in the following evening. Ever heard the term ‘Listen to your body?’ Well, my body likes to tell me that Krispy Kreme has 3 new flavours of doughnuts and if I hurry, I can pick up a box of 12 before they close for the night.

 As you can see, I don’t put a lot of stock into this mantra.

So what effect then, does aerobic exercise have on our health?

Aerobic exercise can be summed up as an activity (in this case, walking, running or biking) that allows you talk comfortably whilst it is being performed. You may break a sweat and will likely still receive the aforementioned endorphin release that comes as part of the package, but you will not be bestowed with any of the adverse health effects. Quite the contrary actually..

Aerobic exercise has been shown to protect against inflammation. That’s right, you can actually reverse the ill effects of a highly stressful day of work, nights of no sleep and (to a degree) the poor food choices you may or may not make.

But what about staving off CVD?

Now here’s a really important point to consider when choosing which form of exercise you are going to dedicate your limited time to-

High intensity, anaerobic (without oxygen) exercise does not increase the strength of your heart or efficiency of your cardiovascular system in the same way that low intensity aerobic (with oxygen) exercise does.

Yes, high intensity training raises the heart rate rapidly, but this does not mean that the heart is necessarily adapting in the way you think it might be.

A high heart rate could be the result of a myriad of different factors. Having someone jump out of a closet to scare you is certainly a good way to raise the heart rate, but this is not an indicator of the body performing more work and it is of absolutely no benefit to your health or fitness.

A critical factor of cardiac adaptation to exercise is Preload (the amount of blood flowing into the heart). Raising your heart rate without adequate Venous Return (rate of blood flow back to the heart), doing high intensity workouts such as 20 rep back squats or burpees and hill sprints, results in minimal preload. This means that only a portion of the heart (Left Ventricle) receives enough stimulus for adaptation and growth, whilst the remainder of the heart remains wholly unchanged. In order for the entire heart and its support system to adapt simultaneously, we must increase the rate of blood flow back to the heart. A larger return of blood causes the heart to swell in order to accommodate the increased Preload. This in turn causes the walls of the entire heart to adapt and grow stronger. This is where the true health benefits lie, and aerobic exercise is the ONLY way to do this.

There are certainly health benefits to be gleaned from high HIIT. It burns plenty of calories in a short period of time and is more muscle sparing when compared to longer duration aerobic training etc. But, having coached more than my fair share of clients over the years, I can tell you this: The average person, for whom working out is not the single greatest priority in their life, will not push themselves to the degree that is needed to receive the benefits of all out, balls-to-the-wall training. Why not give them something that doesn’t scare them off and offers more benefit long term than back to back Tabata workouts?

Assuming the above made sense, I have hopefully made my case for lower intensity exercise. Steady walking/jogging or biking will build a stronger heart, reduce inflammation, lower blood pressure whilst increasing blood flow and as a nice bonus will make your body much better adapted to using glucose and fat for fuel. In fact, aerobic exercise is the most calorically expensive of all forms of exercise, costing about double that of an hour of intense lifting.

But isn’t throwing on a pair of trainers and hitting the road a good way to get injured?

Like most forms of exercise, running is surrounded by dogma that just will not lay down and die. Yes, people do suffer from running related injuries, just as Football and Rugby players suffer from torn cruciate ligaments or damage to their menisci. It is not uncommon for Weightlifters to incur SLAP tears or herniated discs from time to time. Hell, even Swimming isn’t safe. Shoulder issues are a particularly common occurrence, alongside swimmers knee and the discomfort of muscle cramping. And don’t even get me started on Tennis. Stepping on to the court carries with it the same degree of risk as being dropped headfirst into a danger zone on the island in Battle Royale. Considering the amount of torn rotator cuffs, hamstring tears, wrist issues and elbow issues I’ve seen after years of working at a health club, it amazes me that the insidious tweaks and niggles that accompany this barbaric sport have flown under the radar for quite so long.

And while we’re at it, how many people do you know, who have never worked out in their lives before that have bad backs or dodgy hips? Plenty. The fact is, Injuries are a part of life, and avoiding exercise is no guarantee that you will be immune to them.

If running is a risk factor for injury, it’s often down to the fact that most people don’t know how to run. As with anything, it is a skill that requires practice.

If you’re a heavier individual and you decide one day to strap on a pair on Nikes and go run 6 miles with no prior experience, you are open to stress fractures, shin splints and cramping. Allow me to lay out some basic tips to help you avoid such problems.

5 Important Tips

  1. Get a heart rate monitor. This is probably one of the most crucial keys to success when attempting to implement this type of training. We will discuss how to use this later.

  2. Get a good pair of shoes. As a heavier individual (Over 200lb’s) there will be an incredible amount of force being absorbed by your ankle, knees, hips and back as your foot impacts the tarmac. Now is not the time to join the barefoot movement or buy a pair of Vibrams, however I would not recommend buying massively cushioned trainers either, as these will allow you to heal strike without much pain- that’s fine until you end up with a stress fracture 6 weeks down the line. ASICS make some of the best shoes available today. Feel free to contact me for a recommendation.

  3. Be mindful of your form. Keep your elbows tucked in, chest puffed out and chin up, whilst taking short strides. Keeping your feet underneath you as opposed to striking too far out in front will minimise risk of injury. This is not necessarily conducive to running fast, but it is to staying healthy. Do not look down at the ground. Imagine there is a piece of string pulling your head up throughout your run.

  4. Only run twice per week to begin with. Do not be tempted to do more. Once will be a 30 minute heart rate zone 4 jaunt on the road and the other will be a 60-90 minute zone 2 Trail Walk/Run. Supplement another 2 days with a 20 minute zone 2 recovery row, a short interval session such as 30 seconds of sprinting followed by 30 seconds of rest for 3 rounds on the bike, or a couple of one hour dog walks.

  5. Learn to run SLOW. This is how best to do so…

      Heart Rate Monitor/Zone Work:

    Running with a watch and heart rate strap may sound like an inconvenient and unnecessary burden, especially for the new runner.

    Can you get away without these tools? Certainly you can, but it requires a level of intuition that beginners and those accustomed to hard exercise may not possess.

    My first easy run I ever completed after competing as a heavyweight powerlifter was prescribed as a ‘zone 2’ jog.

    I had been waiting on beginning this new phase of training for a few weeks and had envisioned myself gliding down the road like a Kenyan elite – fast and elegant.

    The actual experience was a shock, to say the least…

    You see, for me to stay in ‘zone 2’ for the duration of my run, actually required little more than a fast paced walk. If I ran, my watch would bleep at me to tell me to ‘slow down’. I begrudgingly wandered down the road and back again in my running gear, tempted to fake a limp to indicate to passers by that this was the reason I was not flying along at my standard 6 minute mile pace.

    Depending on your level of fitness, this may very well apply to you.

    First Run Mistakes

    Here’s how the first attempt from a new runner- or someone coming back to fitness after a few years lay-off, generally goes:

    You begin. You know not to go too fast out of the gate and praise yourself for demonstrating restraint when you realise after a few minutes that your breathing is feeling a little more laboured than you expected. You push on. The first ten minutes feel more uncomfortable than initially expected and you pray that you can make the next five without stopping- at that point you can turn around and walk back if you need to. Your thoughts turn to an unrelated topic and before you know it you’ve hit the fifteen minute mark and surprisingly, everything feels easy. You’re cruising along like you’ve been doing this your whole life – could it be that you were ‘born to run’?

    You continue on, watching your feet strike the ground quietly beneath you and you feel thankful that you’ve come back to fitness. Maybe you could sign up to a half marathon next month? Twenty minutes pass and according to your program, this run should be over. But when you’re feeling this good, why not keep going? By the twenty five minute mark the initial discomfort you felt is starting to set in again. Your thoughts return to those of pain and the feeling of numbness in your shins. Your feet feel like they have concrete blocks attached to them. The once perfect stride you possessed has been reduced to a loud, ugly stomp, your face grimacing as you resist the urge to walk, but resistance is futile.

    You finally arrive home, and in hindsight, you conclude that you probably should have stuck to your original plan of no more than a twenty minute run, but hey, no harm done- you can resolve this minor issue next time.

    You go to bed, still enthused and borderline excited for your next training session.

    On awakening the next morning you are aware of a nagging pain in your foot.

    You hope it will go away.

    By the time your next session arrives the pain is still there, but being the ‘glass half full’ type of character that you are, you’re certain that it will dissipate after a few minutes out on the roads.

    You last all of ten minutes before the pain becomes so bad you are reduced to a hobble.

    Welcome to your first running related injury.

    You can either rest it completely for at least a couple of weeks or try again in a few days. The former is just enough time for your new found enthusiasm to wane, leading you to cut short your career as a runner. The latter will accomplish the same, but in a much shorter time frame.

    Believe me when I tell you that you almost certainly do not have the genetics to take a ‘Forrest Gump’ approach to running.

    Be smart. Build your capacity by starting slow and with short distances. Your body will adapt, but not by being thrown in at the deep end.

    Be mindful of your form.

    One trick to improve your running economy and reduce risk of injury when you begin to tire, is to think about your cadence. Download a cadence app and set it to 180bpm. Only play it when you are far enough in to your run that you notice your form begin to slip. This will help to keep your form from completely deteriorating and reduce the risk of injury.

    Another good reason to work to a Zone 2 pace is down to the fact that this is where you will most efficiently build your aerobic base and strengthen the heart in an optimal fashion.  Running too fast will elevate you out of the fat burning state and into another where glucose becomes the primary source of fuel. At this point we are not receiving the heart swelling benefit of steady state work, and worse still, the sympathetic nervous system – which has dominated your stressful day of work – is back in charge. Goodbye recovery.


    The best tip to avoid running injury I ever received was to take to the trails.

    If you choose to run exclusively on the roads, you risk the chance of an overuse injury.

    If your gait is less than optimal, repetitive foot striking on concrete or tarmac can eventually lead to developing any number of ailments.

    Running on uneven terrain allows your foot to land in a slightly different position every time you strike the ground. This helps to strengthen all the muscles, joints and ligaments of the foot and ankle, which in turn increases durability and reduces the risk of future injury.

    Landing on mud and grass helps to cushion the landing and reduce the forces being absorbed by the body. The act of running through tall grass, wheat fields etc. forces you to pick up your feet- improving running form and actively engaging the muscles at the back of the body- an area which is usually highly underdeveloped in most runners. Running downhill causes damage to the quad muscles and a greater degree of DOMS (delayed onset muscle soreness). This is crucial to building stronger legs and delaying the onset of fatigue in longer runs.

    The technical nature of trails also help to improve core strength, proprioception and balance.

    Why I prefer to run and where to go without being seen!

    There are numerous reasons I prefer to run over cycling. The first is cost. Considering that we are trying to make the transition to total health and fitness as effortless and non interferal as possible, I also believe that is shouldn’t cost the earth to accomplish either. A good bike, helmet and clothing can be expensive. Running, on the other hand, at first requires only a pair of shoes.

    Secondly, if you do not have cycle lanes or paths in the vicinity of your house, you will have to take to the roads. Needless to say, the increased speeds you travel at- not to mention the greater distances- increase the risk for accident and injury. Yes, as mentioned before, risk is a part of life and inherent to undertaking physical activity. But nonetheless, this may be a factor for you. Here in the Uk there is no love lost between cyclists and motorists. Because of this, you can expect little consideration from irate drivers if you’re a nervous newbie, cycling too far from the curb or perhaps a little wobbly. Cars truly do bring out the worst in people.

    Hopefully this article has been of some help in guiding you toward a lifetime of enjoyable, injury free running, and with spring just around the corner its the perfect time to lace up and enjoy the great outdoors!

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Holly Rush
Holly Rush
GB Marathon/Ultra Runner Team Silver European Champs & World Mountain Champs 8th Commonwealth Games ASICS UK FrontRunner Manager Marathon Talk Podcast Co Host Coach

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