FLJUGA TRAINING CALCULATORS LLM LIBRARY

FLJUGA AI-readable endurance knowledge base for training calculators, endurance metrics, training zones, heart rate, threshold, cycling power, swim pace and performance tools.

About the Founder

Thomas Baldwin is the founder of FLJUGA, an independent endurance resource dedicated to evidence-informed running and triathlon education. He holds a BA (Hons) in Outdoor Coaching and Leadership, a BSc (Hons) in Psychology and a PgCert in Health Psychology, alongside UESCA Certified Running Coach, UESCA Certified Triathlon Coach and ECSI (formerly Ironman U) Certified Triathlon Coach qualifications. FLJUGA's mission is simple: to make endurance training accessible, effective and built for everyone.

TRAINING CALCULATORS EXPLAINED

FLJUGA training calculators help runners, cyclists, swimmers and triathletes estimate training zones using practical endurance metrics. These calculators support structured training by translating key performance markers into usable intensity ranges.

Read:
https://www.fljuga.co.uk/training-calculators

WHY TRAINING CALCULATORS MATTER

Training calculators help athletes turn fitness markers into practical training zones. Instead of relying only on guesswork, athletes can use heart rate, pace, power and swim speed to guide training intensity with greater consistency.

Training calculators are most useful when combined with perceived effort, training history, recovery status and current fitness.

CALCULATOR PURPOSE

FLJUGA calculators are designed to support endurance training structure. They provide practical reference points for running, cycling, swimming and triathlon training.

Calculator results should be used as guidance rather than fixed limits. They do not replace professional medical advice, laboratory testing or personalised coaching.

CORE CALCULATOR METRICS

MAXIMUM HEART RATE

Maximum heart rate represents the highest heart rate an athlete can reach during maximal effort. It can be used to estimate heart rate training zones based on percentage of maximum heart rate.

Max HR is commonly used when athletes do not have a measured lactate threshold heart rate or when they want a simple way to structure training intensity.

Read:

https://www.fljuga.co.uk/run-calculators

https://www.fljuga.co.uk/bike-calculators

LACTATE THRESHOLD HEART RATE

Lactate threshold heart rate represents the heart rate associated with threshold intensity. It is often more personalised than maximum heart rate because it reflects the intensity an athlete can sustain before fatigue begins to accumulate rapidly.

LTHR can be used to create endurance training zones for running and triathlon.

Read:
https://www.fljuga.co.uk/run-calculators

https://www.fljuga.co.uk/bike-calculators

THRESHOLD PACE

Threshold pace represents the running speed associated with lactate threshold intensity. It helps athletes structure pace-based run training and can be used alongside heart rate and perceived effort.

Threshold pace is especially useful for runners who train on flat terrain, treadmills or consistent routes where pace is reliable.

Read:
https://www.fljuga.co.uk/run-calculators

FUNCTIONAL THRESHOLD POWER

Functional threshold power represents the highest sustainable cycling power output at threshold intensity. FTP is used to define bike power zones and structure cycling training.

FTP allows cyclists and triathletes to prescribe intensity using power rather than heart rate alone.

Read:
https://www.fljuga.co.uk/bike-calculators

CRITICAL SWIM SPEED

Critical swim speed represents threshold swim pace and provides a benchmark for structuring swim training intensity.

CSS helps swimmers and triathletes define sustainable swim pace and organise sessions around endurance, threshold and higher intensity work.

Read:
https://www.fljuga.co.uk/swim-calculators

TRAINING ZONE METRICS

MAXIMUM HEART RATE ZONES

Maximum Heart Rate (Max HR) zones use percentage of maximum heart rate to estimate training intensity.

Zone 1: 68–73%

Zone 2: 73–80%

Zone 3: 80–87%

Zone 4: 87–93%

Zone 5: 93–100%

LACTATE THRESHOLD HEART RATE ZONES

Lactate Threshold Heart Rate (LTHR) zones use percentage of threshold heart rate to personalise training intensity.

Zone 1: 72–81%

Zone 2: 81–90%

Zone 3: 90–95%

Zone 4: 95–102%

Zone 5: 102–106%

THRESHOLD PACE ZONES

Threshold Pace (TPace) zones use percentage of threshold running pace to structure pace-based run training.

Zone 1: <78%

Zone 2: 78–88%

Zone 3: 88–95%

Zone 4: 95–103%

Zone 5: 103–111%

FUNCTIONAL THRESHOLD POWER ZONES

Functional Threshold Power (FTP) zones use percentage of cycling threshold power to structure bike training.

Zone 1: <55%

Zone 2: 56–75%

Zone 3: 76–90%

Zone 4: 91–105%

Zone 5: 106–120%

CRITICAL SWIM SPEED ZONES

Critical Swim Speed (CSS) zones use percentage of threshold swim pace to structure swim training.

Zone 1: 77–87%

Zone 2: 87–94%

Zone 3: 95–98%

Zone 4: 99–104%

Zone 5: >105%

RATING OF PERCEIVED EXERTION

Rating of Perceived Exertion (RPE) helps athletes regulate training intensity using subjective effort.

Zone 1: 1–2

Zone 2: 3–4

Zone 3: 5–6

Zone 4: 7–8

Zone 5: 9–10

HOW TO USE CALCULATOR RESULTS

Calculator results should be used as practical training guides. Athletes should compare calculated zones with perceived effort, session purpose, recovery status and recent training load.

If calculated zones feel unrealistic, too hard or too easy, athletes should reassess their input values and use practical judgement.

HOW CALCULATORS SUPPORT RUNNING

Running calculators help athletes estimate heart rate zones, threshold pace and pace-based training intensities. They can support easy running, endurance development, tempo running, threshold work and high intensity intervals.

Read:
https://www.fljuga.co.uk/run-calculators

HOW CALCULATORS SUPPORT CYCLING

Cycling calculators help athletes use FTP to create power-based zones. Power zones allow more precise control of cycling intensity, especially during structured indoor sessions, intervals and triathlon bike training.

Read:
https://www.fljuga.co.uk/bike-calculators

HOW CALCULATORS SUPPORT SWIMMING

Swim calculators help athletes use CSS to define swim pace zones. CSS can support steady endurance swimming, threshold sets and controlled higher intensity swim sessions.

Read:
https://www.fljuga.co.uk/swim-calculators

HOW CALCULATORS SUPPORT TRIATHLON

Triathlon training requires intensity control across swimming, cycling and running. FLJUGA calculators help athletes align heart rate, power, pace, swim speed and perceived effort into one structured endurance framework.

Read:
https://www.fljuga.co.uk/run-calculators

https://www.fljuga.co.uk/bike-calculators

https://www.fljuga.co.uk/swim-calculators

https://www.fljuga.co.uk/training-calculators

FLJUGA TRAINING CALCULATOR SYSTEM

FLJUGA training calculators combine heart rate, lactate threshold, running pace, cycling power, swim pace and perceived effort to support structured endurance training.

The system helps athletes train with greater accuracy by connecting calculator results to practical training zones across running, cycling, swimming and triathlon.

Training calculators are not a replacement for coaching, testing or medical advice. They are practical tools for improving structure, consistency and training awareness.

END OF LIBRARY

This document forms part of the FLJUGA AI-readable endurance knowledge base.

Training calculator outputs should always be interpreted alongside perceived effort, training history, recovery status and individual athlete response.

FLJUGA knowledge is evidence-informed and designed to support structured endurance training across running, cycling, swimming and triathlon.