Boulder Center for Sports Medicine
The Mapleton Center311 Mapleton Avenue (North side entrance) • Boulder, CO 80304
Phone: 303-544-5700
Physiology Testing
Lactate profile testing is used to determine an athlete's lactate threshold (LT). Simply put, the LT is the most important physiological marker for success in endurance sports. The best training programs use an accurate measurement of lactate threshold to determine individual training intensities. Training at the appropriate intensity can greatly improve your LT, which is an important predictor of sustained endurance performance. Multiple testing of LT can assess the effectiveness of your training over several months.
VO2 max (aka maximum oxygen uptake) is an excellent indicator of aerobic fitness. VO2max is the fastest rate at which your body can use oxygen to make energy. The higher your VO2max is, the better your potential for endurance performance. Serial VO2 max testing can also help assess the effectiveness of your training on aerobic capacity.
Have you ever wanted to know how many calories you actually burn when you exercise? The number of calories you use depends on how hard you exercise: the higher the intensity, the more calories you burn. But as the intensity changes, there is also a shift in the percentage of carbohydrate and fat used. The FUEL test measures how many calories your body needs for exercise at different intensities, as well as the proportion of fat and carbohydrate burned. As your fitness changes, so will the amount and type of fuel your body uses at any given effort. Therefore, repeat testing will help you scientifically monitor your progress. Your FUEL results will assist you in developing a personalized nutrition strategy to meet your goals for improved fitness, weight loss or to gain a competitive edge.
Anaerobic power is assessed during a 30-second test on a cycling ergometer. (The longest 30 seconds of your life!) Peak power output and average power output are determined during the Wingate test. This test measures your peak anaerobic sprinting performance.
The goal of supplemental oxygen training is to allow an athlete to train at the same intensity that they would do at sea level. Athletes use supplemental oxygen training sessions to improve their performance during interval training sessions, without suffering from the effects of higher altitude. Many athletes use supplemental oxygen training to prepare for sea level competitions or help peak their fitness.
FAQ's - Physiology
With these tests we can evaluate your fitness level, make exercise recommendations including heart rate as well as power/speed training zones, to help you meet your goals and, with subsequent testing, measure your improvement. The best exercise recommendations are based on your own individual response to exercise, not on a generalized formula. These tests are valuable because they are a controlled, scientific measurement of your own body's response to exercise at a range of intensities. The information gained from these tests can help you improve your health, your sports performance or both. Furthermore, we can evaluate your current exercise regime in terms of the effects of its volume, duration and intensity.
We will also help you gain a greater understanding of exercise principles, so that you can apply this knowledge yourself to your workouts.
- These tests can help anyone who wishes to get the information they need to train smarter to meet their fitness goals, whether for improving health or for sports performance enhancement. Here are some examples of typical clients:
- Recreational athlete: someone who trains and competes mainly for the sheer fun of it, but still wants to improve and have some structure and purpose in their training.
- Elite athlete: to fine-tune each training bout, avoid injury and overtraining, monitor changes in fitness status, gain a competitive edge through application of sport science principles
- Former couch potato: someone who's decided it's time to get fit, and knows that a proper exercise regime is crucial to one's physical and emotional health; wants to be informed and make the most of exercise time.
- Overtrained athletes: athletes who notice their performance is getting worse, notice a change in mood, get sick more easily than before, or have other signs that might suggest overtraining. We can also help healthy athletes avoid overtraining.
- Someone who's not getting results: one who's been exercising for a while, but isn't seeing much improvement anymore; wants to learn how to change their exercise to continue improving.
- In short, our doors are open to everyone.
If you want to learn specific training intensities, then the Lactate Profile is the best test for you. This is the ‘Gold Standard' used by athletes, especially elite athletes, to prescribe and monitor their training. The Lactate Profile measures your body's response to exercise of gradually increasing intensity. This test yields precise, individualized training information that can be used to hone your exercise bouts for optimal improvement. Changes in your fitness and performance can be measured with serial lactate testing over time.
If you are primarily interested in determining your fitness level, we'd recommend the VO2max test. VO2max is important because it is the prime indicator of your cardiorespiratory fitness, an important indicator of overall health. VO2max can be improved with proper training, but everyone has genetic limitations; being re-tested a few months after your initial test can measure the effect of your training on your cardiorespiratory fitness. If you are interested in the training recommendations from the lactate profile in addition to knowing how many calories you are burning during exercise, and how many of those calories are from fat and how many are from carbohydrates then the FUEL test is for you. We can also perform a VO2 max test in addition to the FUEL test, at a discounted rate.
After a gentle warm up the testing starts at a low level of intensity, about equal to a nice easy workout. (The level is adjusted to match each person's ability.) Then every few minutes the intensity increases. On the treadmill we increase speed first, then grade; on the bike we increase the wattage.
The Lactate Profile consists of a series of four-minute stages, or exercise periods at a constant exercise level. Each subsequent stage is slightly harder than the previous. At the end of each stage a finger stick is performed and a small sample of blood is taken. The blood is analyzed for lactate concentration. We also record your heart rate and your subjective perception of the effort. After several stages, there will be a large rise in blood lactate. You will reach this point below a maximum effort, though well trained athletes may be close to their max at the final stage. We use the information from each stage to gauge the effectiveness of your training thus far, and to give you exercise recommendations.
The VO2max test begins at a workload you can easily handle, and gradually gets more difficult. It's relatively short, but you'll eventually get to the point where you're working as hard as you can. It's a good idea to be very well rested for this test! All along we measure how fast your body is consuming oxygen. This rate of oxygen consumption (VO2) rises as you work harder. Your VO2max is the highest rate your body can consume oxygen, usually very close to your level of maximal exertion.
Maybe... but it doesn't really matter; see the next paragraph. If you're doing a Lactate Profile test, you won't be working as hard as you can, so you won't get to your maximum heart rate. You will come very close, or even reach it if you do a VO2max test though. However, you might get your heart rate even higher when you are outside, which is normal. That is why we call the highest heart rate seen in the lab the ‘peak heart rate', not maximum heart rate.
We do not emphasize learning maximum heart rate during these tests. This is because we prescribe individual exercise intensities based on the Lactate Profile or on VO2max. This method is much more precise because it is based on your own body's response to exercise, not on a formula designed with average values or fixed percentages which may be more intense for some and less intense for others.