How hard should the exercise be? There are two ways of assessing this, i.e. the ‘Talk Test’ and the heart rate Training Heart Rate.

The simplest way is to use ‘The Talk Test’ which uses your ability to hold a conversation with someone as a measure of your exercise intensity. There are three levels:

 

• Level 1 - If you can hold a conversation with someone quite easily, without feeling at all out of breath, you are not working hard enough. Try harder!
• Level 2 - If you can hold a conversation, but feel a bit breathless, this is the correct intensity. Keep it up!
• Level 3 - If you find it very difficult to speak at all, you are working too hard. Ease up!

 

So whatever physical activity you choose, Level 2 is where you should be. Moreover, you should feel pretty much back to normal within 10 minutes of stopping exercise and, if you don’t, you are pushing yourself too hard.

The slightly more involved – but most accurate - indicator of exercise intensity is your Training Heart Rate, or pulse rate, expressed in beats per minute (beats/min). Everyone has a maximum heart rate that is related to his or her age – the Age Predicted Maximum Heart Rate (APMHR). This is simply the fastest your heart can beat. A simple way to calculate your APMHR is to subtract your age from 220, i.e.

APMHR = 220 – Age (in years)

So if you are 50 years old, your APMHR is 220-50 = 170 beats/minute. This means that however hard you exercise, your heart will not beat any faster than 170 beats/min.

But how does this help in determining exercise intensity? Scientific studies have shown that the intensity of effort required for effective aerobic training is in the range of 60 – 75 per cent of the APMHR. This 60-75 per cent heart rate range is called the Training Zone. Training Zone Heart Rates for different age groups are shown in the table below:

Age	Training Zone Heart Rate	APMHR
(years)	(60-75% of APMHR)	(220-Age)
20	120 – 150 beats/min	200
25	117 – 146 beats/min	195
30	114 – 142 beats/min	190
35	111 – 139 beats/min	185
40	108 – 135 beats/min	180
45	105 – 131 beats/min	175
50	102 – 127 beats/min	170
55	99 – 124 beats/min	165
60	96 – 120 beats/min	160
65	93 – 116 beats/min	155
70	90 – 113 beats/min	150
75	87 – 109 beats/min	145

As you can see, if you are 50 years old, your Training Zone is between 108-135 beats per minute. What this means is that to get maximum benefit, you need to exercise with your heart rate somewhere between 102 and 127 beats/minute. When you begin your exercise programme, aim for the lower end of your Training Zone heart rate (60 per cent) during the first couple of months. As your fitness improves you can gradually work up towards the upper limit (75 per cent). After six months, you can exercise above this level – as high as 80-85 per cent of your APMHR if you wish, but you don’t have to work that hard to stay in good condition.

Since you are using heart rate (or pulse rate) to measure exercise intensity, you obviously need to be able to take your pulse accurately – a procedure that requires a little practice. After a while, you will become quite good at estimating your heart rate without having to take it.

Nowadays and even easier option to monitor your heart rate, is to purchase an electronic pulse monitor. These are an excellent investment and allow you to monitor your own heart rate very accurately. A special belt is worn around the chest – although this is not uncomfortable – which picks up the electrical signal from your heart. This signal is then sent to a wristwatch that has a large display, making it easy for you to see what’s happening at any point during your exercise period. Any good quality sports shop will stock a range of pulse monitors – but you don’t need the most expensive model in town. Keep it as simple as possible!

Taking your own pulse

The pulse is the wave of pressure that passes along each artery following each beat of the heart. There are two places to take your own pulse: over the radial artery at the wrist and over the carotid artery in the neck. To take the radial pulse hold one hand palm upwards and place the pads of the three finger tips of the other hand on the groove on the outer side of the wrist – just above the wrist creases – in line with your thumb. You can feel the pulse quite clearly when your fingers are in the right place.

Most people find it easier to take the carotid pulse during exercise. To do this, first feel your Adam’s apple, then move your fingers about one and a half inches either side of this and you will feel the carotid pulse.

Never compress both carotid pulses at once.

Using a watch with a second hand count the number of beats you can feel over ten seconds, and multiply by 6. So if you can feel 20 beats, your heart rate is 120 beats per minute. Alternatively you can count over 15 seconds and multiply by 4. Even easier, buy a pulse monitor!