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TRAINING
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LACTATE TEST Lactate Threshold testing allows elite runners to delay the onset of fatigue and utilise their energy stores for when they need it most: the business end of the race; writes Colin Griffin, Running Re-Education Coach, Sports Surgery Clinic. ATHLETES continuously set goals for themselves. It may be to improve their personal best time, or to achieve a milestone such as a 3hour marathon. Once the goal has been established, the athlete and coach must then sit down and plan their training in order to achieve that goal. But how do we determine how fast our key training sessions should be to improve performance? ANSWER: By measuring our lactate threshold and training to improve it. At higher exercise intensities, lactate and other waste material accumulate in the muscles, which cause fatigue and a greater reliance on glycogen to fuel the performance. But there is only a limited amount of glycogen readily available. Fat, on the other hand, can fuel exercise for several hours. We can train ourselves to utilise our fat stores better and spare glycogen for when we need it most – in the latter stages of a race. This can be achieved by improving the ability to remove lactate as it is produced – the so-called lactate threshold. It is generally accepted that lactate threshold closely correlates with performance. What is Lactate Threshold? The lactate threshold is the highest average speed that an athlete can sustain at which blood lactate readings remain in a relative steady state - also known as the Maximal Lactate Steady State (MaxLass). The MaxLass value can vary individually among athletes from between 2 mmol to 8 mmol. The best way to determine one’s lactate threshold is to measure it. How do we measure lactate threshold? Blood lactate levels, expressed in millimoles per litre (mmol), can be measured with a portable lactate analyser with only a drop of blood from a pin prick to the finger or ear lobe is required. It helps to know how much blood lactate the athlete can sustain for a given period by measuring blood lactate at regular intervals during a continuous run relevant to their race distance. With the athlete’s individual lactate window established, we can then carry out a lactate step test. This step test can be five or six intervals of 6 minutes duration (1 mile or 2km) at progressive speeds. Starting at the pace of a
‘Run at medium pace in training to run fast in a race’ This statement may sound contradictory, but running endurance intervals at high intensity - well above race pace - is counter-productive and does not train the physiological qualities necessary to sustain race pace. A high accumulation of lactate and increased muscle acidosis increases the risk of overtraining because it deconditions the aerobic system and destabilises the lactate threshold. It is important to maintain control of pace and intensity during training and devices such as a heart rate monitor and GPS technology facilitate that.
training run, the athlete increases their running speed by 8-10 seconds per kilometre, expecting to hit their threshold by the third or fourth interval. Based on the lactate readings, the athlete and coach are better equipped to plan their training. How do we improve lactate threshold? The key focus of an athlete’s training programme should be to improve lactate threshold relevant to race distance. The best way to improve it is to strengthen the structures beneath it. That is, the aerobic energy system. Aerobic endurance runs should be in or around 80% LT. Tempo runs should be at around 90% LT, as the purpose is to run continuously at medium distance (depending on race distance) without accumulating lactate. The interval and fartlek training sessions should be done between 95%-105% of the LT.
A typical example of such a test on a 32.00 10km runner with a MaxLass at 4mmol: 1. 2km @ 3.28 per km 2.5 mmol 2. 2km @ 3.20 per km 3.2 mmol 3. 2km @ 3.12 per km 4.0 mmol 4. 2km @ 3.04 per km 5.2 mmol 5. 2km @ 2.56 per km 6.8 mmol ‘If we are not assessing, we are merely guessing’ The initial lactate step-test provides a baseline measure that can be repeated periodically throughout the season. You don’t have to be an international elite athlete to use lactate testing. The lactate threshold is the main performance-limiting factor for any athlete regardless of what level they compete at. We need to measure it, train it and then reassess it regularly (every 6-10 weeks). Otherwise, how do we know if the training programme is working?
• Lactate testing is available as part of the RUN Elite service and as an individual service at the Sports Surgery Clinic.
Based on the above results, the following training intensities would be recommended for this runner, training specifically for 10km whose lactate threshold (LT) pace is 3.12 per km: Recovery/regeneration runs (70% LT): Aerobic Endurance (AE) runs (80% LT): Tempo runs (90% LT): Fartlek/ high volume intervals (90-95% LT): Race-specific intervals (95-105% LT):
4.35 per km (6-8km) 4.00 per km (10-25km) 3.35 per km (6-12km) 3.30-3.20 per km (3x3km @3.30/1km @4.00 or 4x3km @3.25/ 3 min recovery 3.20-3.02 per km (5 x 2km @3.20/2 min recovery, or 10 x 1km 3.15/90 sec recovery, or 15 x 400m @ 3.02/ 45 sec recovery
For more information call 01 5262030. 26 Irish Runner