Triathlon Regimen logoTriathlon Regimen
Guides LibraryTriathlonSwimBikeRun
CalculatorsGuidesOpen Race Calculator
Quick Help
Editorial TeamContact

Run load planning

Run TSS Calculator

Calculate run Training Stress Score from your session pace and threshold pace to quantify training load, plan recovery, and balance run stress within triathlon training.

Session details

Enter your run session duration, average pace, and threshold pace (from VDOT or a recent 1-hour effort).

Total run time

min
sec

Average pace (per km)

min
sec

Your average pace for the session.

Threshold pace (per km)

min
sec

The fastest pace you could sustain for roughly 1 hour. Use the VDOT Calculator to find yours.

Run TSS (rTSS)

55

Standard training session. Manageable fatigue that fits a normal training week.

Intensity Factor

0.86

Threshold

Distance

8.2 km

Intensity

Threshold

At or near threshold pace. This is tempo-quality effort that builds run-specific fitness.

Load

Moderate

Standard training session. Manageable fatigue that fits a normal training week.

Triathlon training context

• Standard run training load. Allow at least 12-24 hours before a hard bike or swim.

• This load level is typical for most structured triathlon run sessions.

Cross-sport comparison

• A typical 1-hour bike ride at 75% FTP produces about 56 TSS. Your run produced 55 rTSS.

• Run TSS per hour tends to be higher than swim TSS because running allows sustained intensity more easily than water-based exercise.

• Run stress carries more impact cost than bike stress. Equal TSS numbers do not mean equal recovery demands.

• Weekly run TSS of 200-400 is common for age-group triathletes across 3-5 sessions, depending on training phase.

Related tools

VDOT Calculator

Find your threshold pace from race results

Bike TSS Calculator

Compare bike training load

Swim TSS Calculator

Swim training stress from CSS

Race Time Calculator

Plan full triathlon splits

Informational tool. This calculator is for personal logging and awareness purposes only. Run TSS uses average pace rather than Normalized Graded Pace, so results on hilly terrain should be treated as directional. Training load classifications are general benchmarks, not individualized assessments. This tool is not a substitute for professional coaching or guidance.

FAQ

Frequently asked questions

What is Run TSS (rTSS)?

Run TSS quantifies the training stress of a run session using duration and intensity relative to your threshold pace. The formula is rTSS = Duration (hours) × IF² × 100, where IF is threshold pace divided by actual pace.

How is Run TSS different from Bike TSS?

The formula structure is the same, but run TSS uses pace instead of power. Bike TSS uses Normalized Power / FTP for intensity, while run TSS uses threshold pace / actual pace. Equal TSS numbers do not mean equal recovery cost — running carries more impact stress per point.

What is a good rTSS for a training session?

A typical age-group triathlete run session produces 30-80 rTSS. Sessions above 100 are hard key workouts. Long runs may reach 120-200 rTSS. Weekly totals of 200-400 across 3-5 sessions are common.

How do I find my threshold pace?

Threshold pace is roughly the fastest pace you could sustain for one hour. Use the VDOT Calculator with a recent race result, or use a 30-minute time trial and add 5-10 seconds per km to the average pace.

Evidence

References

Related calculators

Keep the next decision close.

VDOT Calculator

Run

Turn a recent race result into practical run training paces, track splits, equivalent performances, and triathlon-aware interpretation.

Bike TSS Calculator

Bike

Calculate bike Training Stress Score, Intensity Factor, and target ride stress with cleaner load guidance for self-coached triathletes.

Swim TSS Calculator

Swim

Calculate swim Training Stress Score from session pace and CSS threshold to quantify training load, plan recovery, and balance swim stress within triathlon training.