Zola Budd: Content

Sky-High Heart Rate


I run 5-10km three to four times a week. I have been doing this for more than a year now. My heart rate is very high when I run. I use a heart rate monitor; in fact, I’ve been using two, as I thought the first one’s reading was wrong, but they both show the same readings! I run very slowly, yet my heart rate is very high throughout the run. For example, yesterday I ran 10km, my average pace was 6:34 min/km, and my average heart rate was 178. Because my heart rate is so high and continues to stay high, I feel exhausted all the time and after 10km I feel like dying! In the beginning, I thought my heart rate will improve as I get fitter, but after a year it’s exactly the same. Please help! – STANLEY LOUW, PRETORIA

Because I do not know your age, gender, state of fitness, or your actual individual Maximum Heart Rate (MHR), it is difficult to comment on whether this training heart rate is indeed high. Here is a link you can visit and depending on your fitness level – you can determine at least an estimate of your MHR – http://www.howtobefit.com/determine-maximum-heart-rate.htm.

There are a few things to bear in mind, however. Your MHR is genetically determined, so it’s your individual number, and there is great fluctuation among people of the same age. It’s sensitive to certain variables such as altitude, drugs, medication, but remains a fixed number, unless you become unfit. It only declines with age in sedentary individuals and tends to be higher in women than men. It cannot be accurately predicted by any mathematical formula, and testing needs to be done several times to determine the exact number.

Given all these factors, you can see that whilst an average training rate of 178 might be very high for a person who has a low MHR, it might be perfectly normal for someone with a high MHR. We can get overly caught up in technology and you might find that BECAUSE your heart rate ‘seems so high’ to you, that you feel worn out. And that had you not known your heart rate – you might have actually felt fine.

So my advice is:
• Try to get an accurate idea of your MHR to see at what percentage of your MHR you are actually training, and if it really is worryingly high – in which case you visit your doctor for a check-up. In fact, for ease of mind, go for a check-up anyway!
• Ensure you are following a scientifically sound training programme.
• Check on your general health status: Are you eating a healthy balanced diet? Are you overly stressed or not getting enough sleep, etc. All these factors can affect how hard a training session feels.

 Modern Athlete Expert
Sport scientist and Health Promotions Manager at the Sports Science Institute of South Africa in Cape Town, and a member of Celtic Harriers with many years running experience, including four Comrades and eight Two Oceans medals.

Skyrun Altitude

I completed my first Salomon Skyrun a while ago and would like to know why I was not affected by the altitude (2700m), despite coming from Cape Town. I did try and keep my heart rate low on the steep ascents, so as not to burn too much glycogen, and I finished day one in 13hours.

The effects of altitude on athletic performance have been extensively researched over the years in order to promote both superior performance and prevent altitude-associated illnesses. There could be many reasons why the altitude did not affect your performance, including genetics, exercising intensity and whether you had acclimatised to the environment beforehand.

The general belief behind altitude and exercise is that when at altitude, the percentage concentration of oxygen is less than at sea level. Therefore, when exercising at altitude, there is less available oxygen to be used/taken up by the muscles, thus you are unable to perform optimally. There is, however, much scientific debate whether the oxygen availability itself impairs muscular performance, or whether it is the brain down-regulating activity in response to it sensing the drop in oxygen concentration.

With the information you have provided you mentioned that you made sure to keep you heart rate down. Heart rate is a good indicator of exercise intensity. This means that you most probably did not push yourself too hard on the steep ascents where you would’ve felt the effect of the altitude the most. Furthermore, it seems that you ran at an average of 5km/h, and taking the slope/gradient into account, it seems that your running intensity was not high enough for you to feel the hypoxic effect of the altitude. Another possible reason was that you managed to acclimatise to the altitude prior to event, i.e. arriving at the destination a few days beforehand.

Exercise scientist at the UCT/MRC Research Unit for Exercise Science and Sports Medicine, based at the Sports Science Institute of South Africa.