4DP Test / Profile
The 4DP test is a cycling field test of four intervals (5 s, 1 min, 5 min, 20 min) that captures sprint, anaerobic and VO2max power alongside FTP.
In our glossary, you will find clear explanations of key terms. Whether technical terms or abbreviations, get the right information quickly.
Acute Training Load (ATL)
Acute Training Load (ATL) is the exponentially weighted average of daily Training Stress Score over roughly 7 days and quantifies short-term fatigue.
Aerobic Decoupling
Aerobic decoupling is the percentage rise in heart rate at constant power or pace over the course of an aerobic session; below 5% is considered stable.
Base Training
Base training is the 8–16 week phase in which aerobic endurance is built: high volume, low intensity, structured into Base I to III with rising intensity.
Build Phase
The build phase is the 6–10 week block after base training in which specific, race-like sessions turn aerobic foundation into race performance.
CarbMax
CarbMax is the power range in which the body oxidises the highest amount of carbohydrate per hour under load, typically quoted as 60–90 g/h.
Chronic Training Load
Chronic Training Load (CTL) is the exponentially weighted 42-day average of the Training Stress Score and is often labelled "fitness" in training software.
Classical Periodization
Classical periodization is the linear progression of training from base to race form in fixed, sequential training phases that build on one another.
Control Metric
A control metric is the measure a training session is planned, paced and evaluated by, such as power in watts, pace per kilometre or heart rate.
Critical Power
Critical power (CP) is the highest power output that can theoretically be sustained without progressive fatigue, sitting close to the anaerobic threshold.
Critical Swim Speed
Critical Swim Speed (CSS) is the swimming speed that can theoretically be held for an extended time, usually derived from 400 m and 200 m time trials.
Data Weighting
Data weighting is the practice of giving individual measurements different influence in an analysis, based on recency, measurement quality or data source.
Data sovereignty
Data sovereignty is the principle that you decide which connected device or app is the authoritative source for each type of data in obseed.
Decoupling tests
A decoupling test measures how much the ratio of heart rate to power or pace drifts over a defined duration at a constant, predefined workload.
Efficiency Factor
Efficiency Factor (EF) is the ratio of normalized power or pace to average heart rate within a session and indicates aerobic efficiency over time.
Energy Provision at Rest
Energy provision at rest is the metabolism without physical load: how much energy the body expends and from which mix of fats and carbohydrates it comes.
Energy Provision in the Body
Energy provision in the body is the set of metabolic pathways by which carbohydrates and fats are converted into ATP, aerobically or anaerobically.
Energy Provision under Load
Energy provision under load is the shift of the substrate mix from fats to carbohydrates, and from aerobic to anaerobic, as exercise intensity rises.
FTP
FTP (Functional Threshold Power) is the maximal power an athlete can theoretically sustain for one hour; the term was coined by Andrew Coggan.
FTP test
An FTP test is a field test that estimates functional threshold power, usually as a 20-minute all-out effort with a 95 percent correction factor.
FatMax
FatMax is the exercise intensity at which fat oxidation reaches its maximum, typically located in lower zone 2 or the low-intensity training range.
Gross economy
Gross economy is the energy efficiency of the whole system of body and equipment: the oxygen cost of one watt of power output at a constant workload.
Heart Rate
Heart rate is the number of heartbeats per minute (bpm). In training it serves as an indirect marker of intensity, fatigue and recovery state.
Heart Rate Reserve
Heart rate reserve is the difference between maximum heart rate and resting heart rate. It is the basis of the Karvonen formula for training zones.
Heart Rate Variability (HRV)
Heart rate variability (HRV) is the fluctuation in the time between consecutive heartbeats (RR intervals). It is a key marker of recovery and load.
Individual Periodization
Individual periodization is the planning of training phases according to diagnostically determined needs of one athlete rather than a fixed template.
Intensity Factor
Intensity Factor (IF) is the ratio of normalized power in a session to threshold power. It shows how hard a workout was relative to the threshold.
Lap
A lap is a manually set or automatically generated time or distance segment within a training session that is analysed separately from the whole.
Leg Spring Stiffness
Leg spring stiffness (LSS) is the spring stiffness of the leg while running, the ratio of peak ground reaction force to leg compression, expressed in kN/m.
Macrocycles
A macrocycle is the longest planning block in a periodised training plan, usually a season or a full training year, built around one main goal.
Mesocycles
A mesocycle is a training block of three to six weeks inside a macrocycle, built around one clearly defined training emphasis such as base or threshold.
Microcycles
A microcycle is the smallest planning unit in training, usually one week, in which loading and recovery days are arranged in a fixed, repeatable pattern.
Normalized Graded Pace
Normalized Graded Pace (NGP) is the flat-ground equivalent of a run pace that would produce the same load as the actual pace including hills and surges.
Normalized Power
Normalized Power (NP) is the constant power output that would have produced the same physiological load as the actual, fluctuating power of a ride.
Peak and Plateau Weeks
Peak and plateau weeks are 1–2 deliberately overloaded training weeks with 20–40% more load, typically in a training camp or right before the taper.
Performance Parameters
Performance parameters are the stored profile of thresholds, power and heart rate zones with which training is planned, controlled and analysed.
Periodisation
Periodisation is the long-term division of training into phases with different emphases so that fitness peaks at the main goal instead of by chance.
Preparation Phase
The preparation phase is the first block of a season: 2–4 weeks of diagnostics, strength and mobility work so the body can tolerate base training.
Recording Sessions
Recording sessions means capturing a workout with a sports watch or head unit; recording rate and lap settings determine how well it can be analysed.
Recording Sessions: Cycling
Recording cycling sessions is largely automatic; what matters is the auto-lap setting, sensor pairing and the correct bike profile with its power meter.
Recording Sessions: Other Endurance Sports
For other endurance sports, watches offer installable or custom sport profiles whose recording and auto-lap settings should be adapted to the discipline.
Recording Sessions: Running
Recording running sessions usually works automatically and well, provided recording rate, auto-lap distance and paired sensors are set before the start.
Recording Sessions: Strength Training
Recording strength training requires regular use of the lap button to separate exercises, sets and rests, and to log repetitions and the weight moved.
Recording Sessions: Swimming
Recording swim sessions requires choosing pool or open water and the pool length beforehand; in the pool, sets are captured manually with the lap button.
Recovery Phase
The recovery phase is the 3–14 day period directly after an important race in which training is cut sharply so muscles and metabolism can regenerate fully.
Reverse Periodisation
Reverse periodisation turns the classic phase sequence upside down: intensity and speed are trained first, and volume is layered on afterwards.
Session
A session is one complete recorded training unit, from starting the watch to saving the file, uploaded as a single dataset for training load analysis.
Speed
Speed is distance covered per unit of time, usually given in km/h in endurance sport, and serves as an external control variable on flat courses.
Sport Profile
A sport profile is the setting on a sports watch or recording device that defines which sport is recorded and which sensors, zones and metrics apply.
Statistical Terms
Statistical terms in training are the measures used to smooth, compare and classify data series: rolling mean, standard deviation, z-score and baseline.
Structure
Structure in training is the deliberate arrangement of load and recovery at every level, from the season plan down to the segments of a single session.
Tapering
Tapering is the 1–3 week unloading period before a race: volume drops by 40–60% while intensity is kept, so fatigue clears and fitness shows on race day.
Training Control
Training control is the recurring cycle of planning, executing, recording and analysing sessions, aligned to a clearly formulated goal and fed by data.
Training Cycles
Training cycles are recurring structures in the training build-up: macro-, meso- and microcycles order load and recovery from months down to days.
Training Intensities
Training intensities divide load into three tiers (LIT, MIT, HIT) so that sessions and races can be prescribed and analysed by their objective load.
Training Phases
Training phases are blocks of a season plan, each with its own goal, volume and intensity distribution: from preparation through base and build to taper.
Training Planning
Training planning is the process from diagnostics through periodisation to the weekly plan, turning load, recovery and goals into an executable structure.
Training Stress Balance
Training Stress Balance (TSB) is the difference between chronic training load (CTL) and acute fatigue (ATL) and shows how fresh an athlete is on a day.
Training Stress Score
Training Stress Score (TSS) quantifies session load from duration and intensity relative to threshold power; 60 minutes at threshold equals 100 points.
Training Zones
Training zones are the performance bands between recovery and maximal effort, defined as a percentage of a threshold or by measured physiological markers.
Transition / Off-Season
The transition is the 2–6 week bridging phase between two race preparations or at season end: loose structure, low volume, focus on strength and mobility.
Zone Names and Models
Training zone names and models are not standardised: zones 1 to 7, ReKom to maximal range, and models by Coggan, Friel or metabolic testing all differ.