Running marathons – How to control your own pace
Choosing the right pace for you during the marathon is the key to knowing how well you will finish the race. First of all, it is important to understand what is happening to your body as you go through the long distance of the marathon.
You will be running quite comfortably at first (hopefully anyway!), due to your marathon training and your carbohydrate stores (glycogen stores). However, your supply of accessible ‘fuel’ is limited, and as you reach the 17-mile mark and beyond, you need to draw energy from your body’s protein and fat to keep going. At the same time you are also fighting dehydration. You can lose 2 to 3 pounds per hour of body weight while sweating during the race.
Now imagine it’s a windy day or a hilly ride (or both!). Your energy output has to increase if you want to maintain your target pace and time. However, this may mean that you will use up your available energy reserves even before you hit the 17-18 mile mark.
The same goes for the temperature and humidity level during the race. If these are high, you will sweat more and be more affected by dehydration. This will negatively impact your performance by 10-15%, which translates to approximately 1 minute per mile. In other words, you’ll be slowing down…
Marathon runners “hit the wall” because their glycogen stores are depleted and they feel very weak. This feeling will be aggravated by the effects of dehydration. At this point many runners have to stop and walk just to continue. Obviously, they won’t be able to meet their marathon time goal.
So, knowing all this in advance, the wise marathoner will carefully assess race conditions at the start of the race. If it’s hot, it’s best to start slower until you’ve reached a steady running pace. The same goes for the headwind. You should also consider your running form after six miles or so. Are you relaxed and feeling as good as you should at this early point in the race? If not, it’s time to slow down for a while to see if you recover.
To successfully complete a marathon, you must run as far as you can within your body’s comfort level. That may sound like an oxymoron when we’re talking about 26.2 miles, but it’s possible! If you can get to the 16-mile mark without too much stress, then you have a good chance of finishing the race without too much trouble.
The key point is to start with a target pace range in mind, and not an absolute goal like 3hrs 45mins. For example, you can choose a pace between 8:30 and 9:00 minutes per mile (for a marathon time in the range of approximately 3h40m to 4h). Then adjust your pace according to the conditions and your own running ability on marathon day. It’s usually best to start on the slow end and then pick up the pace as you go through the race.
Give this a try and you might be pleasantly surprised at how well you complete the race.
