Wednesday, 10 October 2012

Heart Rates Part 2: Maximum Heart Rate

So, have you worked out your resting heart rate yet? 

Well, now that you have that, the next important figure to work out is your maximum heart rate. Why, I hear you ask? (Well, probably not, but you should, because it is an important question).

Maximum heart rate is not the rate that you should aim to exercise at, just to make that clear at the beginning. However, a lot of training programs work on a series of exercises that focus on maintaining a particular % of your maximum or your heart rate reserve (more on that in a later post). Therefore, to use these programs most effectively you need to know your max. 

Many of you would have been told to calculate your maximum heart rate based on a formula that uses your age. 

The most common formula I've come across is 220 - your age = maximum heart rate. (Some now adjust that to 226 - your age for females).

Therefore, since I'm 29, my maximum would therefore be 191 or 197.

Online calculators like the one at My Dr ask only for your age and from that tell you what you should be working out at, apparently using the 220 formula as they recommend 191 for me.  

Anyone else see any problem with this? That all males and females, regardless of exercise history, health, anything like that all have the same maximum heart rate? True maximum heart rate does not change like resting heart rate does, but still, there must be more variation than that!

Considering 2 years ago I used to sit on 198/199 for roughly half an hour once a week, I some how doubt that those figures given are my maximum. (By the way, totally do not recommend working at that level, I just had little choice.)

There has been a lot of research into the area, which I think has been summarized nicely by Brian Mac, who then allows you to enter your age (though didn't ask for gender, which is strange as that is one variable he discusses), sport and level (average/elite) and will then give you a range of answers based on the different research he discussed. Highly recommend you check it out to show how much formulae can vary.  

However, while using a formula can be alright to give you a general idea, since they can vary +/-20 beats, it's probably worth doing some testing yourself. 

An accurate, but expensive, way is to go to a sports clinic and actually have a maximum heart rate stress test performed. They hook you up to a whole lot of fancy equipment and make you run on a treadmill. The results come with a lot of other important and interesting information, so is worth the money. The only downside that I've heard from friends (I haven't done it myself) is that you are doing a one off test. If you are slightly sick that day, aren't prepared to push yourself as hard as you otherwise might, etc. the results can come in lower than they might otherwise be. 

The other cheaper, but less accurate on a once off test, is to perform similar tests yourself. 

NOTE: I recommend having someone with you when you do this, in case of a medical emergency.

Also, you will need a heart monitor for this. Using the ones on a treadmill isn't really practical, as it is not safe to run with your hands on the grips over a speed of about 6.5km/h. A band around your chest with a watch that you can program with your age and gender is much better. (I'll do another post later on different models of heart rate monitor. For this, if you haven't got one yet, try to borrow a good one off a friend, or you can pick up cheap ones at Big-W and places like that usually for around $30 (the expensive ones start at around $200, so you are saving a lot).)

Polar (heart rate monitor company) gives these two tests to try out: (note that they expect you to know what 85% of your maximum heart rate is already, which is a bit counter intuitive, but you can use a formula for a basic number).

A sub maximal test is not as specific as the VO2 Max test, however it is more individual than the age based formula and it can be performed readily in the field.

Example 1: Running
Ensure the Polar heart rate monitor is set to display heart rate in beats per minute. You must first perform a 15-20 minute warm up with your heart rate gradually reaching 85% of your maximum heart rate.
Now, on a running track or other open environment, perform a 2 minute run at maximal effort, recover for 2 minutes (either remain stationary or slow walk) and then perform a second 2 minute run at maximum effort. Take note of the highest heart rate value reached either in the first or second interval and add 5 additional beats to the highest value. This number can now be used as your maximum heart rate.

Example 2: Cycling
Ensure the Polar heart rate monitor is set to display heart rate in beats per minute. You must first perform a 15-20 minute warm up with your heart rate gradually reaching 85% of your maximum heart rate.
Now, at the base of a hill which has a steady gradient of approximately 4-5%, perform a 3-4 minute seated climb at maximal effort, in a gear that allows you to maintain a cadence of 60-70rpm. Take note of the highest heart rate value reached. Add 5 additional beats to the highest value and this new number can be used as your maximum heart rate.

These are good as they are pretty simple, and as long as you have a heart rate monitor, you can do it almost anywhere, any time. 

However, as a rower, my favourite is based on the Concept 2 suggestion. It is hell, but I think more accurate. Please note, this is for generally healthy, fit people without any heart conditions.

They suggest a Step Test. The Polar method is two sets of maximum effort, which is good that they did it twice but most of the time when we jump from a lower rate to a higher rate, we don't really know how far our maximum really is. This test, on the other hand, gets you to work up step by step until you utterly cannot continue ('until you blow' is their wording).

Most gyms will have a Concept 2 rowing machine, but make sure you know the proper technique before trying to do this test or you might end up straining something or taking out someone else's eye (oh you laugh, but not as much as I laugh at the people who think they can row at my gym!). 

It's easiest if you know how to set the machine to do 1.30min intervals. If not, I recommend having a friend next to you monitoring your heart rate and reminding you to step up ever 1.30mins. 

Start off rowing at an easy rate that gives you a heart rate of 140bpm. If you have already warmed up, you only need to do this for 1.30mins, but if you haven't warmed up already, I personally recommend just doing a few more minutes to make sure you don't injury yourself. 

Now, if you can put your display so it is showing watts, every 1.30mins step up 25 watts. If you can't get it to display watts (though it's quite simple, just press the 'change display' button until it cycles through to watts) then you can just do it based on split using the table below.

Watts  25  50 75  100  125  150   175
500m  4:01.0 3:11.3  2:47.1 2:31.8
2:12.6  2:06.0 2:00.5
 225 250  275  300  325  350  375
500m 1:55.9  1:51.9  1:48.4   1:45.3 1:42.5  1:40.0  1:37.7  1:35.6
 Watts  425 450  475  500  525  550  550  600
500m 1:33.7 1:32.0 1:30.3
1:28.8 1:27.4

And as the name 'Step Test' suggests, you keep stepping up every minute and a half until you feel like you are going to die. 

Well done, that's your maximum heart rate. (Though, some people do recommend adding on 5bpm all the same.)

So, this week's challenge: using either one of the Polar Methods, or if you are feeling brave the Concept 2 method, test out your maximum heart rate.

No comments:

Post a Comment