Physiology FAQ’s favicon

What are the benefits of SBT?

• Reduced risk of overtraining
• Greater efficiency of training
• Training targeted at your individual physiological requirements
• Greater physiological ability to tolerate the demands of training
• Improved performance
• Improved recovery rate

What does SBT actually test?

Lactate is a biomarker that is produced during exercise. It is produced through the glycolytic pathway, when there is too much pyruvate than can be oxidised aerobically. As blood lactate levels increase it demonstrates increasing use of anaerobic energy systems to sustain the level of work. Lactate can be used as an indirect marker to measure metabolic changes and as a useful index of exercise intensity.

SBT uses this lactate data to analyze efficiency across 8 energy systems that your body uses as fuel for activity. SBT utilizes world leading physiological profile testing (PPT). The PPT system was developed in the USA to assess metabolism, exercise physiology, biochemistry, and bioenergetics to optimize sporting performance.

I’m not an elite athlete, can SBT benefit me?

The great thing about SBT is that anyone can benefit from it. It doesn’t matter if you are a world class athlete or have just started training for your first event. Across all sports and sporting levels the principles behind SBT remain the same. SBT optimizes your individual performance based on your physiological capabilities. Using SBT won’t make everyone an Olympian, but it can ensure that everyone is maximizing their training. It reduces the risk of overtraining, and makes sure systems are primed for the requirements of training.

What are BioEnergetic Power Scores (BEPS)?

BEPS is a reference value that determines if each energy system has the capacity to provide sufficient fuel for activity. These reference values have been created over the past 15 years from 150,000 samples. Every activity from sleeping to completing an Ironman can be defined along the human bioenergetic power continuum. Testing gives an idication of what BEPS value you require for your chosen activity and goal. As part of your report you will get a BEPS score and graph.

This shows that when initially tested this athlete was totally lacking fuel in AF, PAC, ANRC-2, and ANRC-1 energy systems. This resulted in reduced functional aerobic capacity and a reduced maximal anaerobic capacity. With a 12 week SBT program this athlete improved their 800 meter time from 2:15 to 2:08.

To get a better understanding of the in-depth science behind these principles follow this link; See more

How do I read my BEPS results?

As part of the data analysis we will give you a rating in relation to functional capacity to perform at your required level. These ratings are divided into categories:


This does not mean that the individual is not a talented athlete. What it is demonstrating is that there is negative adaptation to training load. It demonstrates that the current balance of training and lifestyle is inappropriate for their needs. An individual’s metabolic and physiological state is constantly changing and can be influenced by many factors. Without physiological testing it is hard to know what training load is appropriate.
Their BEPS graph would show only ONE available energy system to produce the fuel for ALL their activity where ideally you need a minimum of 6 working systems. It’s like a car working on only one cylinder; still able to move but not performing well. Non-Functional athletes have a negative energy balance (between aerobic and anaerobic energy contribution) and are in an inadequate state of recovery. The appropriate training prescription will address this current metabolic state regardless of the cause.


These athletes haven’t quite got the balance right. They have adapted to the stress put on their body by shutting down energy systems. This results in a negative energy balance; less energy in than energy out. This means for certain activity levels they will be using inappropriate energy sources. If we use the car analogy again, it would be like a race car trying to run on standard unleaded petrol. Your body is able to adapt to using an inappropriate fuel source, but it means it is not functioning as well as it could. The first aim for these clients would be to increase the number of energy systems they have available, this will give them availability to use different fuels for different activities.


Dependent on their activity, functional athletes might have enough energy systems available to contribute to their activity. Different activities have different requirements in terms of their energy systems and as such require different fuels. For these individuals we would look to increase the ability to work at the specific levels required for their activity, whilst increasing the availability of the fuel to sustain activity at different intensities.


This is the ideal state for people to be in prior to starting a training block. It represents a positive energy balance between aerobic and anaerobic energy systems, meaning they are getting the appropriate balance between training and recovery. Their BEPS graph would show all 8 systems working well. With these individuals we would look at their activity specific requirements with the goal to strengthen the energy systems that provide the largest contribution to their activity.

What can I expect from the testing?

• Testing takes approximately 30-40 minutes but may take 60 minutes for beginners.
• Your finger will be pricked with a sterile instrument in order for us to collect drops of blood.
• You will perform 5-8 intervals. The speed of the intervals will start very easy and become progressively harder with the final interval being at maximal effort. The speed of these are based on ability, and these details are given on testing day.
• Please being a heart rate monitor to wear during testing. After each interval heart rate will be recorded.
• The tester will clean your skin and squeeze your pricked finger to produce a drop of blood so a reading can be taken. Occasionally a second prick is needed to produce the required drop of blood if you are cold or dehydrated.
• You will then perform the next interval. The process will be repeated until all intervals are completed.

What happens after testing?

After testing we analyse your results and produce a report highlighting your strength and weakness. Depending on how much input you require, I.e. level 1 or 2 packages, we will either provide guidance around training parameters to target the most appropriate energy system, or provide a detailed daily training program to ensure you maximise your training.

How often should I be tested?

The results from your PPT and any subsequent training recommendations are accurate to meet your current needs. However, as you train your body adapts and so does your requirements for future training. As such, we recommend that athletes re-test every 3-4 months or at the end of a training block. This will ensure up-to-date information on how the body is adapting to training stimulus. Retesting allows us to make adjustment to optimize your performance as required. It also provides for longitudinal information that creates better understanding of how your body adapts to training and stressors. This allows for increasingly accurate prescriptions with each test performed.

Why do I need a heart rate watch?

Heart rate indicates the daily stress the body is managing and how hard the body is working, even if the rate or power output is slower than normal. SBT uses precise workloads to achieve specific physiological objectives. It is based on gaining improvement in 8 different energy systems to improve overall performance. If you were to train only at a prescribed pace every day, this would not take into consideration the environmental effects on your energy systems. Keeping within prescribed HR zones gives an effective measure of your bodies overall work effort, and will allow specific training of the individual energy systems. This ensures appropriate loading no matter what the conditions.

Do I need to stick to my HR when running up a hill?
Yes. We are using your heart rate as measure of how much stress your body is under. When training specific systems we need to ensure the stress on your body is appropriate for the system we are training. There are a number of different situations that would cause an increase in heart rate when running, such as hills, heat, or work related stress. These external factors can increase your heart rate because your body is under more stress, so working harder. To ensure you are training the correct system you will have to accommodate these external stressors to ensure you stay in your target heart rate zone. This means you may need to slow down to stay in your ideal training zone for that day.
What can PPT tell me?

The testing data from PPT is applied specifically to you as an individual to help you achieve your goals. PPT can assist you to get the best out of your training with a reduced overall training load as it will increase efficiency of training, leaving more time for recovery or leisure activities. It can help you plan your training phases and training loads as these are not just dependent on individual physiological readiness and not just based on the level of your athletic experience, a set time in a training phase or number of weeks until peak performance.

What can PPT tell me as a Coach?

Coaching is an art, but science can greatly benefit any coach looking to take the guesswork out of program development and produce peak performance when it counts. PPT offers coaches a greater understanding of the contribution and importance of glycolysis, aerobic and anaerobic metabolism. It offers information on how physiology can be trained and therefore maximized. The value, interaction, and balance of energy systems is necessary for success because there is a strong contribution of both aerobic and anaerobic power in most sporting codes.

Repeated testing over a period of time can provide coaches with a wealth of physiological information that can pinpoint the training stimulus for maximum response in each athlete. SBT can provide valuable data and recommendations to identify athletes with greatest athletic potential. It can also provide measureable data to demonstrate physiological power gains made in the off season for each athlete.

Does SBT replace my coach?

No, nothing can replace the experience and knowledge a good coach has. What SBT gives your coach is the necessary information to develop a truly individualised training program. One that is sensitive to the changing needs of your body. This will ensure you are able to maximise the benefits from your training.

Why can't I just train using functional threshold power (FTP) instead?

FTP is the maximal power output that an athlete can sustain over 60-minutes. FTP is determined by calculating average power outputs over a set timeframe, then using a percentage of these outputs as your training zones. This training information is largely based on averages, and is generalized across populations. It does not provide any indication about how YOUR body is tolerating these loads.
One of the main issues with this training method is that athletes are often required to work at or near threshold levels, for repeated bouts, with no information on how their body is tolerating these loads. These levels of training are extremely taxing on the body and can result in overtraining and reduced performance.

SBT takes the guess work out of training. We can use your FTP score as a indication of what starting value to use for the first interval in your SBT test.

Why can't I just train using heart rate training zones instead?

Heart rate training zones are useful as it gives an indication of how hard your body is working during training. The issue with using heart rate as a sole measure is that it is based on standardized data. As no two people are the same, without having performed physiological testing we cannot say that two athletes who are working at the same heart rate are using the same energy system. Without the individualized information that PPT offers you are essentially guessing, which can result in over or undertraining.

After you have completed your testing you will have accurate individualized information on the heart rate training zones that reflect YOUR individual needs.

What is lactate threshold and is it dangerous to go above this threshold?

What is Lactate Threshold?

Lactate threshold is described as the highest intensity of exercise that can be maintained where lactate production matches lactate clearance. It can be described as the point where we “switch” between aerobic and anaerobic energy systems. This terminology is widely used in physiology to explain a complex process in simple terms.  In reality there is no single point where we switch from aerobic to anaerobic systems, it’s a constantly changing continuum. Lactate threshold is not a particularly important measure by itself, it is merely a point on the continuum of your lactate profile.  Aerobic to anaerobic energy systems both contribute to all exercise, however, the relative contribution changes with exercise intensity.

Is Testing above Lactate Threshold Dangerous?

There is no danger in testing above lactate threshold, rather it affords greater safety as it gives accurate data rather than extrapolated data above threshold. This accurate data can be used to safely prescribe velocities, wattage and loads of training for those higher energy systems. It is in these higher energy systems where people are often overstimulated, resulting in impaired efficiency or performance. But in order to gain a complete picture of an athlete, we must expose them to similar exercise intensities as they would experience during training and competition. This means we test to exhaustion. Gaining this data means that we can determine exactly how the body copes with higher intensity exercise, and allows us to develop individualized plans to meet the body’s needs.

Where can I learn more about SBT principles?

For more information check out the Go Athletics website and blog.,
Or book in for a one-on-one consultancy service where we can provide specific advice and education to meet your individual requirements.