RUN YOUR BEST HALF IN A HALF
Running your best in a half-distance race is not a simple task. The half-distance might be one of the most challenging races to prepare for and execute well because pacing can be a real challenge.
It’s complicated because the half-distance falls into a very awkward space between our two ventilatory thresholds. The first threshold is at about 65 to 70 per cent effort. The second, more easily identifiable threshold happens around 85 per cent effort. A full-distance race is best executed around the first threshold. Shorter events, like an standardor sprint-distance, are best executed just below, at, or just above the second threshold. Therein lies the problem – a half-distance race lands somewhere in the middle, which can make the formula for success a tricky one to figure out.
The length of time it will take you to complete the race is usually a good place to start. If you plan to finish in six hours or more and are expecting to run the half-marathon around two hours, you will likely need to race around that first 65 per cent threshold. If you are a professional or one of the top age group athletes and finishing around four or five hours with a half-marathon time in the 70- to 90-minute range, you can definitely push the effort up between the two thresholds more aggressively.
Once you have nailed down the effort that is appropriate for you it becomes easier to apply specific training loads and nutrition strategies that will help you maximize your performance. Training specificity, impact tolerance, speed work, nutrition and your mental game are a few of the key factors to consider when aiming for a fast half-marathon in a half-distance race.
The first step is to practise running at your goal pace, particularly during brick sessions (running off the bike). During the six- to eight-week lead in to your race you should be executing a workout once a week that mimics the pace and effort you want to sustain. This includes a longer bike workout with appropriate length intervals at the wattage and/ or heart rate you wish to sustain on race day. During these rides you should be practising your nutrition to make sure that you are taking in sufficient amounts of carbohydrate, water and sodium. The run off the bike does not need to be long. Building up to a set of six one-mile repeats at your goal pace on a short rest interval is more than sufficient to provide a training stimulus.
The limiting factor, when running off the bike, usually has as much to do with your ability to handle the impact and fatigue in your legs as it does with your aerobic fitness. Hill running (both up and, in particular, down) is a great way to build up this tolerance. Downhill running increases the impact on your body and acts as an added stress. A word of caution, though: that increased impact from downhill running can potentially lead to injury. Make sure your plan is progressive and that the length of time spent running downhill is monitored closely. The grade should not be overly aggressive, either. A gentle decline is enough.
Long runs are also a great way to develop your ability to handle the stress on your body. Make sure that you do some of your running on pavement (if the race is going to be on roads). Your longest run should definitely exceed the time you expect to run during the race. If you plan to be in the 70- to 90-minute range, your long run can be about two hours. If you estimate that you will run two or more hours during the half-marathon, your long run can be closer to two and a half hours. The risk of injury usually increases with increased mileage and may start to outweigh the physiological gains you will make running beyond two and a half hours.
Including some speed work is also a great strategy. In the context of this article let’s consider “speed work” as anything faster than your goal race pace. Once a week consider including a workout with shorter, faster intervals at, or exceeding, your second threshold. Anything in the two- to five-minute range, with equal rest, for a total of 15 to 25 minutes of work is sufficient.
Nutrition for your best half-marathon starts on the bike. You must consume carbohydrate, water and sodium on the bike if you want to have success on the run. Focus on small amounts, frequently, and aim for roughly 1 g of carbohydrate per kilogram of body weight, along with 500 to 1,000 ml of water and 500 mg or more of sodium per hour. This can usually be covered by a bottle of sport drink