Training

Looking INSCYD

How INSCYD testing goes beyond FTP to inform cycling training, fueling, and intensity.

What Is INSCYD Testing

INSCYD is performance analysis software that uses test data to build a metabolic profile: a picture of how your body produces energy, uses fuel, and responds to different cycling intensities. It gives your coach information about aerobic power, glycolytic power, threshold, and fat and carbohydrate use.

At Métier, we use the INSCYD Power Performance Decoder, or PPD, to calculate this profile from recorded cycling efforts. Your power output supplies the test data; the software models the physiology behind it.

For cyclists preparing for a race, a demanding ride, or a stronger season, that information gives training a clearer direction. It helps us identify what needs attention and connect each session to the demands of your goal.

INSCYD vs. FTP: What a Threshold Test Misses

Functional Threshold Power, or FTP, is a useful benchmark for sustained cycling power. It provides a reference for training intensity and a practical way to track performance over time.

A common FTP test estimates threshold from 95% of your average power during a 20-minute effort. That calculation is an estimate, and FTP should not be treated as interchangeable with a directly assessed lactate threshold or maximal lactate steady state.

The larger limitation is what the number leaves out. Two cyclists with the same FTP can have different aerobic capacities, glycolytic power, and fuel demands. Their threshold power may look identical while their responses to a long climb, repeated attacks, or several hours of riding differ.

INSCYD provides a stronger basis for individualizing training than FTP alone because it examines those underlying differences. You can still use FTP as a benchmark while using metabolic testing to decide how to improve.

What Your INSCYD Metabolic Profile Reveals

An INSCYD report connects several measurements and calculated metrics that matter to cycling performance:

- VO₂max: Maximum oxygen uptake, a key marker of your aerobic capacity.
- VLamax: Maximum lactate production rate, a marker of glycolytic power. This matters for explosive efforts and influences the balance between sustained power and fuel use.
- Anaerobic threshold: INSCYD calculates the intensity associated with maximal lactate steady state, where lactate production and clearance remain balanced.
- FatMax: The intensity at which your fat oxidation rate reaches its maximum.
- Carbohydrate combustion: Estimated carbohydrate use across different power outputs.
- Lactate accumulation and recovery: Modeled rates of lactate accumulation above threshold and clearance below it.

These results need to be read together. A high VLamax can support the acceleration that decides a criterium, while a lower VLamax can favor sustained endurance performance. Neither is automatically better. The useful question is how your profile matches the riding you want to do.

"Two cyclists with the same FTP can have different aerobic capacities, glycolytic power, and fuel demands."

How Metabolic Testing Changes Cycling Training

Specificity means choosing training that addresses your physiology and the demands of your event. A criterium, a mountain road race, and a 200-mile gravel ride require different priorities, even for cyclists with similar FTP values.

Metabolic profiling helps a coach choose those priorities and set intensities around the system being trained. Aerobic capacity, glycolytic power, and fat oxidation each provide information that a percentage of FTP cannot supply on its own.

Consider over-under intervals, which alternate efforts above and below threshold. INSCYD's lactate accumulation and recovery curves help a coach select the power, duration, and recovery needed to create the intended session. Two riders completing the same workout at the same percentage of FTP may experience different physiological demands.

Retesting adds another useful layer by showing how the profile changes through training. Alongside ride data and athlete feedback, it helps a coach assess progress and adjust the next block.

"INSCYD estimates carbohydrate combustion across a range of intensities. Combined with fat oxidation data, it helps your coach assess the fuel cost of your planned pace"

How Metabolic Testing Changes Cycling Training

Specificity means choosing training that addresses your physiology and the demands of your event. A criterium, a mountain road race, and a 200-mile gravel ride require different priorities, even for cyclists with similar FTP values.

Metabolic profiling helps a coach choose those priorities and set intensities around the system being trained. Aerobic capacity, glycolytic power, and fat oxidation each provide information that a percentage of FTP cannot supply on its own.

Consider over-under intervals, which alternate efforts above and below threshold. INSCYD's lactate accumulation and recovery curves help a coach select the power, duration, and recovery needed to create the intended session. Two riders completing the same workout at the same percentage of FTP may experience different physiological demands.

Retesting adds another useful layer by showing how the profile changes through training. Alongside ride data and athlete feedback, it helps a coach assess progress and adjust the next block.

INSCYD Testing and Cycling Coaching at Métier

Métier offers INSCYD metabolic testing in Seattle and remotely. The PPD uses recorded power from prescribed maximal efforts, so testing can take place indoors or outdoors without a gas-analysis mask or blood lactate sampling. Following the supplied protocol and recording accurate power data are essential.

The results are calculated physiological estimates. INSCYD publishes validation work comparing its outputs with reference testing methods, and accuracy depends on the protocol and quality of the inputs.

After your test, we provide a report covering your metabolic profile, power targets, and fuel use. Choose the consultation option to work through the results with us and connect them to your goals, or share the report with your existing coach.

"Metabolic testing is especially useful for cyclists preparing for an event, working through a plateau, or seeking clearer direction from their training."