In the last edition, club coach Lawrence Bookham introduced himself and gave some advice to those starting out. This time, it’s all about improving your fitness and busting some of that jargon…
There are lots of scientific, and some not so scientific terms and definitions to understand, so I thought I would try to help explain some of these.
VO2Max (measured in ml of oxygen per Kg of bodyweight) represents an individual’s oxygen consumption. It is a measure of the body’s ability to run fast for extended periods of time. Most runners are unaware of their VO2Max, however the principles for improving running speed, endurance and economy remain the same regardless of knowledge of personal VO2Max.
The best way of improving Vo2max is by spending as much time at close to max (100%) as is reasonably possible. This is achieved by running intervals at a specified pace (or intensity 98% max HR) with restricted recoveries.
The reason these should be run at 98% is because you if do go above Max, you will not be aware of it, eg, if you run at 110% Max, your HR will be at 100% (Max), it can’t go above it obviously.
It is important to understand lactate threshold training as this is what improves endurance in long distance running. Lactate is produced by the metabolism of carbohydrates and contrary to popular belief, is an energy source. It is now understood that muscles produce lactate, which the liver then converts into glucose to provide additional energy back to exercising muscles.
The production of lactate increases with effort and can reach a point where lactate production out paces the body’s ability to consume it. The exercise intensity where this occurs is known as the Lactate Threshold. Sustained effort at or above this pace (or intensity) can only be maintained for a limited time until the body is no longer able to continue due to hydrogen ions which diminish the muscle’s ability to contract forcing you to slow down.
This is an important pace to understand for long distance races and training to improve speed. Ideally, races of 10 miles and longer are run just below the lactate threshold. With proper training, the lactate threshold can be raised to allow a faster pace over a longer distance. This is best achieved with regular extended efforts at or just below threshold with rest in between to reduce the accumulation of lactate.
This is how energy efficient you are as a runner, or more specifically, how much oxygen your body consumes for given running speed. It is the sum total of many biological factors such as metabolism, the neuromuscular system and the runners bio-mechanics as well as training history. A runner with good economy would use less oxygen than a runner with an inferior economy at the same speed. We try to improve economy with repetition work and strides to train the body to recruit the most effective combination of muscle fibres and therefore reduce wasted motion.
Running Intervals and Repetitions
A common mistake that runners sometimes make in training is running the sessions too hard. The idea that running your workouts harder will make you a better runner is appealing, and seems logical. But it is the incorrect way to do them. Building up a high concentration of lactate in your muscles can only be counter-productive as it will likely shorten the duration and reduce the quality of the workout defeating the purpose of the workout all together.
Working faster than your training pace/ intensity will not give you any more benefit relative to the purpose of the workout.
Intervals (I pace)
The purposes of Intervals are to improve aerobic power (VO2max) by making the body function at, or nearly at the body’s VO2max. It is considered ‘hard’ running for a predetermined amount of time or distance, usually between 1 to 5 minutes, with short rest periods – usually no longer than 3 minutes but needs to be enough to afford recovery for the next interval. These are the toughest workouts we do, and a talk test would mean you should be able to speak one word at a time.
It is important that intervals are run at the correct pace (I) or intensity which you can determine using a training pace calculator. Some calculators will refer to this pace as VO2max training pace. It takes around 2 minutes to reach VO2max when running at this pace assuming that you are starting out at a resting VO2.
The target HR for these are 98% of Max HR. The reason these should be run at 98% is because you if go above Max, you will not be aware of it, eg, if you run at 110% Max, your HR will be only ever be at 100% (Max), as it can’t go above it obviously, you’ll be entering the anaerobic zone (which hurts!) and will probably be unable to reach max on later intervals..training at 98% tells you that are a just below it meaning you will not miss out on valuable time spent at max.
Threshold Intervals (sometimes called cruise intervals)
The purpose of these workouts are to improve endurance by improving the body’s ability to clear lactate. These must be run at your lactate threshold pace (T). This pace would be described as comfortably hard, which means you are working relatively hard, but the pace is manageable for a fairly long time (certainly 20 or 30 mins in practice).
Repetitions (R pace)
The primary purpose of repetitions is to improve speed, and economy of running.
These call for the fastest pace in training (but not maximum effort) and at an intensity that will always elicit maximum heart rate if you stay at that pace. Typically done for short distances (200-400 meters) but with full recoveries – you should not run until you feel you can do it again at the same speed and with good technique. You do not want to be struggling while doing these or good mechanics will be sacrificed.
Use the full recovery to prepare yourself for each effort. Focus on form and staying relaxed: hips forward, lead foot hitting the ground just below your centre of gravity, ~180 steps/minute, etc.
This is a continuous run that lasts typically around 20 minutes held at Threshold pace and is good at building confidence that that you can maintain a fairly demanding pace for a relatively long time. This would normally be in between several easy miles eg: 4m E pace then 3m T pace followed by 3m E.
This a run that comprises of a series of varying paces. The run can be long or short, and can be structured or unstructured. It’s a good introduction to speed work or as an off season workout. I am not that keen on these as training sessions as they are not specific enough.
Put simply, strides are very short repetitions over around 100m -150m with a progressive acceleration up to the desired pace with a deceleration back down, so that the muscles and tendons are only fully extended for a short duration.
Strides are too short to produce improvements in any energy system, but they are useful to improving or maintaining good technique with relatively little stress on the body.
Heart rate training
If you train using a heart rate monitor, it is critical that you know your max heart rate otherwise you will be wasting your time. Do not use formulas, they are inaccurate. The figure for a maximum heart rate can vary greatly from person to person, even in those of the same age. The best way is to conduct a field test by finding a hill and running up and down it hard for 6 minutes.