Look Good, Feel Great : Part 20 - Keep on running

It’s sad but true - your aerobic capacity declines dramatically with age. As it does so, you usually do less physical activity, walk slower and become more easily tired with the slightest exertion. For example, if you have to use 75 percent or more of your aerobic capacity just to walk to the shops or climb the stairs, not only will you be knackered doing these activities on a regular basis, you’ll have very little energy for anything else. At the same time you’re hit with the double whammy of declining muscle mass and increasing fat. So a less efficient heart has to contend with an increased workload! Basically, as your aerobic capacity diminishes, life just gets harder and harder!

Total bummer!

The scary bit is how fast our aerobic capacity declines - we lose an average of 8.3 percent of exercise capacity per decade in our 40s, rising to 23.2 percent per decade in our 70s and above

Wake up folks – unless you’re doing something about it, this is the rate your heart’s wearing out at!

The good news is that, with an effective aerobics programme, you can raise your aerobic capacity 15 percent to 25 percent, which translates into you being capable of fitness levels of someone 10-20 years younger. Even better, as you maintain exercise, even though your aerobic capacity will decline, it does so at a slower rate than if you did no exercise at all. At any given age someone who exercises will have a higher aerobic capacity than someone who is a couch potato. In other words, their heart will be stronger, and wear out less quickly

In Part 10 - Stepping Out we looked at the three ways of increasing your body’s ability to burn calories and therefore fat. You can increase the frequency of your workouts, the intensity of your workouts, or the duration of your workouts

By now you’re doing four or more aerobic workouts a week, so there’s little if any scope for increasing the frequency of your workouts, especially if you’re doing a couple of muscle training workouts in addition. In fact, please don’t workout seven days a week – give your body at least one day of rest. If you’ve also upped the duration of your workouts to 45 - 60 minutes, again, it’s difficult to step up this variable

So what’s left? That’s right – you need to step up the intensity of your workout!

Calculating Intensity

Up to now you’ve been using the Perceived Exertion Scale to judge how much effort you’re putting into an exercise:

1 Nothing

2 Very Easy

3 Easy

4 Comfortable

5 A little difficult

6 Difficult

7 Hard

8 Very hard

9 Extremely hard

10 Bloody hell, I’m dying!

This remains a pretty good way of judging intensity even at this stage. However, if you want to squeeze the maximum out of your workouts, you’re going to have to get a little more disciplined in your approach to intensity

And that doesn’t mean just going as fast and hard as possible. If you just floored it at the start of every exercise, how long would you be able to keep it up? One minute? Two minutes? Maybe five minutes? Remember – you need to exercise continuously for twenty minutes in order to burn fat. So simply stepping on the gas as hard as possible isn’t the answer

What you need to do is work at an intensity that’s not too light that you’re wasting the opportunity to burn fat, but not too hard that you can’t get through your full workout. This is known in the trade as your training zone.

How do you find out what your training zone is? The answer lies in our good friend the heart, and specifically in your heart rate, that is to say, the number of times your heart beats in a minute. Doctors have long known that you can tell a lot about a person’s health based on his resting heart rate (RHR). A typical RHR is between 60 and 80 beats per minute (don’t panic if yours is above 80, but if it’s significantly above, say over 100, it may be wise to get yourself checked out by the doc). The better your level of cardiovascular fitness, the lower your resting heart rate will be. The average resting heart rate is 72 beats per minute, with athletes usually having resting heart rates substantially lower than this because their hearts (remember, the heart is a muscle) are more efficient and don’t have to work as hard to get blood pumped around their body. The legendary cyclist Miguel Indurain, for example, was reputed to have a resting heart rate of 28!

How do I find out my Resting Heart Rate?

You can do this by counting your pulse (at your wrist or the side of your neck) for a full 60 seconds. Alternatively, you can use a heart rate monitor (more of which soon). In either case, your resting heart rate should be measured first thing in the morning as soon as you wake up and before engaging in any activity or eating or drinking anything. The best way to do it is to have your watch or heart rate monitor by the side of your bed and take the measurement as soon as you wake up

How to use your Heart Rate to burn fat

To do this you need to do 3 things:

1. Calculate your Maximum Heart Rate (MHR)

2. Determine training zones

3. Incorporate the above into your workout

How to calculate your MHR and training zones

There are a couple of ways to calculate your maximum heart rate and, from that, your training zones:

The Age Predicted Method :This is the simpler of the two methods. You simply deduct your age from 220 to get to your estimated maximum heart rate (MHR). So if you’re 50, then using 220 - 50 = 170, your estimated MHR is 170 beats per minute

But as we’ve seen you cannot and should not exercise at maximum heart rate. So a further calculation is needed to get to your training zone, which is anything from 60 to 85% of your MHR depending on your objectives. In fact you should really now be thinking of three training zones, to be used on different days, or for different parts of your workout, as follows (for a 50 year old):

1 60% - 70% of MHR (best for endurance) 102 - 117

2 70% - 80%  of MHR (best for improving aerobic fitness) 117 - 136

3 80%+ of MHR (best for improving strength and for maximum calorie burning) 136+

The Karovnen Method

This is a more accurate method, it’s reliant on you knowing your resting heart rate (RHR). As with the age predicted method, you determine your maximum heart rate using the formula of 220 minus your age. For a 50 year old, this is 220 – 50 = 170. Now you have to determine something called your Heart Rate Reserve (HRR) by subtracting your RHR from your MHR. So if our sample 50 year old has an RHR of 75 beats per minute, his HRR will be 170 – 75 = 95 beats per minute

Next select and apply the intensity range you want to work at from:

1 60 - 70% moderate

2 70 - 80% harder

3  80%+ even harder

So for our 50 year old for Training Zone 1 this works out at 95 x 60% = 57 to 95 x 70% = 67

Lastly add back your RHR to your HRR to determine the target heart rate  57 (HRR) + 75 (RHR) = 132 – lower limit,  67 (HRR) + 75 (RHR) = 142 – upper limit

You may feel that this is a pretty ball-aching method compared with the simplicity of the Age Predicted Method, but you’ll note that there’s a fair bit of difference in the results from the two methods. The reason is that

Karvonnen uses data personal to you, i.e. your RHR. The Age Predicted Method is OK for beginners, but as you get a little more serious, you should switch to Karvonen

Regardless of which method you use, it’s important to understand that unless you’ve really gone the whole hog and had your heart rate measured professionally (where medicos give you something called a graded treadmill test, hooking you up to a bank of monitors and gradually running you faster and steeper until you literally drop from exhaustion – not particularly recommended!), the resulting target heart rates are still only guidelines – they are estimates. You’ll still need to use your own good judgment about how the exercise feels and how your body is responding. Use common sense: if you’re working in your target heart range and it feels ridiculously easy, then don’t be afraid to increase the intensity. On the other hand, if it feels incredibly difficult, don’t hesitate to decrease your intensity. Don’t cheat, don’t be macho, use your loaf!

Incorporating training zones into your workout

Once you know your training zones you’ve really unlocked the secret to successful aerobic workouts. Without them you might work yourself too hard, too often and burn out, or work too long without getting your heart rate high enough to see results. Either way you’ll be disappointed. Paying attention to your heart rate will allow you to work with the intensity you need. For each workout make sure you’re at least in Zone 1 for the majority of the time, and get into Zones 2 and 3 when needed

Measuring Intensity

Knowing the intensity you need to workout at is one thing, but how the devil can you measure your heart rate when you’re pounding away on the treadmill?

• You could periodically check your pulse at your wrist or neck to see if you’re within your target range while you’re exercising

• Then, if you’re below your target heart rate, you could increase the intensity by increasing resistance, speed or incline

• If on the other hand you’re above your target zone, you could decrease your intensity

YEAH RIGHT – how practical is that?! Can you imagine taking a full 60 second count while rowing? Of course not!

Enter one of the best investments you’re likely to make in your fight against fat - the heart rate monitor. One of these babies is the best way to measuring your heart rate during exercise. You wear what’s in essence a (very

ugly) wristwatch and chest strap

• The chest strap transmits your heart rate to the wrist monitor via something called telemetry. This allows you to check your heart rate while you workout without having to pause every few minutes to take your heart rate

• The very simplest heart rate monitors simply display your current heart rate, so you can use them to find out your RHR as well as your heart rate during exercise. The more you pay, the more features you get

• If you can stretch to it, get one where you can programme in your lower and upper training zone limits. As you exercise, if you go above or below these settings, the heart rate monitor starts to beep (some models have different beeps for going above and going below) so that you can adjust your intensity accordingly

• Another feature this type of monitor will have is the ability to give you your maximum, minimum and average heart rates during your workout, useful for monitoring progress as you get fitter. At present they cost from between 50 and 90 pounds. If you’re flush, you can spend a lot more and get monitors that act as stopwatches, give you lap times, split times, send data to your mobile, and, just in case you were thinking of exercising underwater, they are water resistant to depths of 30 metres!

• In addition and very useful for visual checks during your workout, most modern exercise equipment in gyms is now heart rate monitor compatible, so your current heart rate will be transmitted directly to the machine and you can see the reading on the console’s readout!

• If you have one that gives you maximum heart rate, use the highest MHR reading you get to calculate your training zones

Interval Training

No matter what intensity you’re currently exercising at, there’s a technique you can use to burn even more calories. In addition, this technique helps alleviate the tedium of exercising at the same intensity for the whole duration of the exercise

When you do a cardio session at the same pace the whole time, your body goes into what is called steady state. This means that your body has adjusted itself to the speed you are going and tries hard to conserve calories. You’ll be able to avoid this and burn more calories and fat by doing interval training. Interval training is so simple that anyone can do it. All you’re doing is varying the intensity of the exercise at different times during the workout. Here’s how:

• The easiest way to get started is to start off at your target heart rate pace for 5 minutes

• Then take up the intensity on the machine (resistance, speed, elevation, whatever – you can vary this as you like) and go harder and faster for a minute

• Then bring it back down to your original pace for a minute or two or however long it takes for you to recover enough to do it again

• Another easy way to introduce yourself to this kind of cardio without killing yourself right off the bat is simply to keep changing your speed and intensity level every two minutes or so - go up and down – and challenge yourself

• This will trick your body into burning more calories since it can’t achieve steady state. Obviously if you can keep a record of changes in intensity (the easiest way is, say, two minutes off, one minute on) so much the better, as you can then start ratcheting up the intensity as you make progress

Here’s an example of a 20 minute interval training workout on an upright bike for those who haven’t tried this type of training before:

Resistance Level 3: 5 minutes (warm up)

Resistance Level 7: 1 minute (work interval)

Resistance Level 5: 2 minutes (recovery)

Resistance Level 7: 1 minute (work interval)

Resistance Level 5: 2 minutes (recovery)

Resistance Level 5: 2 minutes (recovery)

Resistance Level 7: 1 minute (work interval)

Resistance Level 5: 2 minutes (recovery)

Resistance Level 3: 3 minutes (warm down)

This is for an exercise bike, but the principle can be applied to any machine or exercise

What’s good about interval training is that the permutations are almost endless. And it’s so easy – most modern exercise machines have several interval training programmes already built in to them, so you don’t even have to do any fancy calculations. Just remember to step up whatever variable is open to you every so often in order to avoid steady state (yes, your body even gets used to interval training!)

Why does it work? Well, it’s all to do with the fact that your body spends time post exercise expending energy. This is commonly referred to as EPOC (Excess Post-exercise Oxygen Consumption) and it means that you consume a great deal more oxygen recovering from the exercise bout than you would have done if you’d just done a steady state workout. This means that you could be burning up to nine times more fat while sitting on the couch later that night than you would have if you’d spent an hour on the treadmill at a moderate pace! Magic!


The logical extension of this has led to a type of interval training called High Intensity Interval Training (HIIT for short), where you work at such an intense level during your work intervals that your body will spend the rest of the day expending even more energy to recover from the ass-kicking you gave it in the gym

Some advocates of HIIT reckon that all you need is 3 minutes of cardio a week, but that’s suspiciously like the siren song of ‘something for nothing’. HITT is simply a natural progression of ‘normal’ interval training that you should be able to sustain for your normal workout of up to 1 hour

The HIIT version of the Interval Training cycle workout might look like this:

Resistance Level 4: 5 minutes (warm up)

Resistance Level 9: 2 minutes (work interval)

Resistance Level 6: 1 minute (recovery)

Resistance Level 9: 2 minutes (work interval)

Resistance Level 6: 1 minute (recovery)

Resistance Level 9: 2 minutes (work interval)

Resistance Level 6: 1 minute (recovery)

Resistance Level 9: 2 minutes (work interval)

Resistance Level 6: 1 minute (recovery)

Resistance Level 4: 3 minutes (warm down)

Of course EPOC happens even after steady state exercise, but the magnitude is negligible. Somewhere between 9 and 30 extra calories are burned after exercise at an intensity of less than 60 - 65% of MHR. So the casual stroll you see some people doing on the treadmill will do next to nothing to increase their metabolism post exercise. If you increase the intensity (and, by the way, duration) of the exercise, EPOC does increase. So the EPOC after moderate exercise (75 - 80% of MHR) will amount to about 75 extra calories. Nothing to get too hyped up about, you may think, but this could add up to an extra 5lbs of fat burnt a year

There’s no doubt that HIIT works, but it’s not a panacea. Don’t be seduced by the promise of something for nothing. Remember that what’s most important for fat loss is the number of calories that you burn, so even if you do a steady state workout at moderate intensity for a long duration, you’re likely to burn far more calories than a fashionably brief HIIT workout, even when the ‘afterburn’ effect from HIIT is factored in. Try both types and mix and match!

Also, be careful – the full, really intense version of HIIT is an advanced technique that is very, very taxing and challenging and not for beginners. Master the fundamentals of aerobic exercise before you even contemplate HIIT

And that’s pretty much all you need to know about aerobic exercise. Well, not quite. As with food there are a few more things you can try to burn off that last ounce of fat

Fine Tuning

Do your aerobic workout first thing

When you exercise, you have to burn off any food still in your stomach before getting to stored body fat. If you do your aerobic workout first thing in the morning on an empty stomach there’s less or no undigested food to use as energy. Furthermore, after your sleep, your body’s stores of glycogen are depleted and you burn more fat when glycogen is low. Also remember that when you do aerobic exercise, your metabolism stays high after the workout is over (EPOC). If you do cardio late in the day, you don’t take as much advantage of this afterburn effect because your metabolic rate drops dramatically as soon as you go to sleep

Another benefit of exercising early is that you get it over with before your day gets going. It’s done and in the bag before the demands of other people cut in or you’re too tired later in the day to be bothered. It’s also easier to make the time for exercise early – it just depends on your own willpower and a good alarm clock!

Alternate low-impact aerobics with high-impact aerobics

It’s a good practice generally, and the more workouts you do per week, the more relevant it is – don’t do high impact aerobics day after day. By high impact I’m referring especially to running, but also to some classes involving lots of jumping and stepping, when your leg joints can take a pounding. Also, on no account just do running as your aerobic exercise – there’s no faster way to get joint and muscle injuries. So vary the types of aerobic exercise you do, not just to protect your joints and muscles but also to ward off boredom! 20 - 30 minutes at a time of any one type of exercise is plenty!


Doing too much aerobic exercise not only puts you at greater risk of injury, boredom or burnout, it also causes your body to adapt to the high volume of training. In much the same way as your body fights your attempts to create an energy deficit by reducing calorie intake, it battles your attempts to create one by doing aerobics. Quite simply, if you do too much aerobics, e.g. daily sessions, for a long enough period, your body completely adapts to the workload and fat loss may come to a screeching halt

So fool your body by alternating periods of high volume aerobic work with periods of low volume work. Have at least one day off a week. Take a whole week off every six weeks. Don’t feel too guilty about taking a two week break when you go on your holidays: compensate by eating and drinking a little less and doing different types of exercise – maybe swimming, walking or cycling. Go on, pamper yourself – you deserve it!

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May 11, 2012

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