Blood Lactate &
Substrate Utilisation
Understand exactly how your body performs under pressure. This advanced test reveals
your true training zones, how efficiently you use fuel, and the exact pace you can sustain —
so you can train smarter, race better, and eliminate all guesswork.
To truly unlock your potential, you need to understand how your body performs under pressure — not rely on guesswork or generic formulas.
Blood Lactate Profiling and Substrate Utilisation testing give you a direct insight into how your body produces energy, manages fatigue, and performs at different intensities.
By measuring your blood lactate levels alongside your respiratory gases during a progressive exercise test, we can identify your true training zones, your sustainable race pace, and how your body uses fuel at every stage.
This allows you to train with precision, fuel correctly, and perform at your highest level.
Advantages of Blood Lactate & Substrate Utilisation
The Performance Lab produces a comprehensive, athlete-specific report that goes far beyond a simple number. You will receive actionable data presented clearly, with expert interpretation included, so you can apply your results from day one.
Eliminating “Junk Miles”
Stop wasting time in the grey zone. Ensure every training session has a specific physiological purpose, whether that is building an aerobic base or pushing your anaerobic limits.
Precision Race Fueling
Eliminate the risk of gastric distress or hitting the wall. You will know exactly how many carbohydrates your body burns at race pace, allowing you to create a customized grams-per-hour fueling strategy.
Accurate Race Pacing
Set realistic, scientifically backed goals for race day. You will know the exact pace or wattage you can hold for hours without redlining early.
Measurable Progress
Re-testing provides concrete data. You will physically see your LT1 and LT2 shift over time, proving that your metabolic efficiency and fitness are improving.
How is the Blood Lactate & Substrate Utilisation Test Performed?
Our testing environment is highly controlled, professional, and tailored to your specific discipline (treadmill running or stationary cycling).
1
Preparation & Baseline
We fit you with a heart rate monitor and a comfortable metabolic mask. We take resting lactate samples to establish your baseline.
2
Incremental Ramp Test
You begin exercising at a very light intensity. Every 4 minutes, we slightly increase the speed, incline, or wattage in a controlled manner.
3
Data Collection
During a short rest period at each stage, we take a small finger or earlobe blood sample to measure your lactate levels. The metabolic mask continuously records your gas exchange.
4
Threshold Detection
The test is sub-maximal, meaning you do not have to go to absolute exhaustion. We stop shortly after you pass your anaerobic threshold (LT2
What is Blood Lactate Profiling?
Lactate is often misunderstood as a waste product that causes muscle soreness. In reality, it is a crucial energy source. However, as exercise intensity increases, your body eventually produces lactate faster than it can clear it. During our incremental step test, we take precise capillary blood samples to track this accumulation and identify your two most critical physiological turning points:
LT1 (Aerobic Threshold)
This is the point where blood lactate just begins to rise above baseline levels. Training at or below this intensity builds your aerobic base, increases mitochondrial density, and promotes recovery. This is your true Zone 2.
LT2 (Anaerobic Threshold / Lactate Turnpoint)
This is the tipping point. Above this intensity, lactate accumulates rapidly in the blood, leading to an acidic environment and rapid fatigue. Knowing this exact heart rate and power/pace allows you to train your threshold and determine your maximum sustainable race pace.
What is Substrate Utilisation?
“Substrate” refers to the fuel your body uses for energy — primarily fat and carbohydrates. Using indirect calorimetry, we measure your oxygen intake and carbon dioxide output to determine exactly which fuel source your body relies on at different intensities.
Finding Your FatMax
Your body stores far more fat than carbohydrates. We identify your FatMax — the intensity where fat burning is at its highest. Training here improves efficiency and preserves glycogen for higher efforts.
The Crossover Point
As intensity increases, your body shifts from fat to carbohydrate use. Knowing this crossover point allows you to plan precise race-day fueling and avoid hitting the wall.
Who Benefits from This Data?
Marathoners Triathletes
- Lock in precise race pace at LT1 and LT2
- Build exact fueling strategies by intensity
For The Cyclists
- Align power zones (watts) with LT1 & LT2
- Optimize interval and base training sessions
Hybrid / Hyrox Athletes
- Balance endurance output and strength work
- Pace runs without compromising lifting performance
Endurance Enthusiasts
- Accurately define true Zone 2 intensity
- Train smarter—not harder—every session
Frequently Asked
Questions
GET IN TOUCH TODAY!
Open Hours
Sun – Fri: Contact for availability
Sat: 6am – 7pm
Location
Killinan, Thurles,
Co. Tipperary
Useful Links
Reservation
(085) 1179316
info@theperformancelab.ie