VéloPeak tracks a set of key numbers that tell you how your body is adapting to training and what you're capable of. They all start from TSS (Training Stress Score) — a measure of how hard each workout was relative to your FTP.
Fitness (CTL)
Chronic Training Load — a 42-day exponential moving average of your daily TSS.
Think of it as your long-term fitness base. It rises when you train consistently over weeks and months, and drops when you rest or reduce volume. A higher CTL means your body is adapted to absorbing more work.
A CTL of 50–70 is typical for an amateur rider training 8–10h per week. Elite amateurs often sit at 80–100+.
Fatigue (ATL)
Acute Training Load — a 7-day exponential moving average of your daily TSS.
This reflects how tired you are right now. After a big training block, ATL spikes. After a rest day it drops quickly. ATL always reacts faster than CTL because of the shorter time constant.
Form (TSB)
Training Stress Balance — simply CTL minus ATL.
This is the number that tells you whether you're ready to perform:
| TSB | What it means |
|---|---|
| > +5 | Fresh — rested and ready to race or test |
| -10 to +5 | Neutral — good for quality training |
| -30 to -10 | Fatigued — productive overload zone |
| < -30 | Overreached — risk of illness or injury |
A negative TSB isn't bad — it's expected during hard training blocks. The goal is to manage it: go deep during build phases, then taper to bring TSB positive before key events.
FTP
Functional Threshold Power — the highest average power you can sustain for approximately one hour, measured in watts (W).
FTP is the foundation of all training zones and every calculation on this dashboard. It is used to:
- Define your 7 power zones (Z1–Z7)
- Calculate TSS for each activity
- Derive W/kg and estimated VO₂ Max
You can update your FTP in Settings > Profile after a ramp test, 20-minute test, or by asking your coach.
W/kg
Power-to-Weight Ratio — your FTP divided by your body weight in kilograms.
W/kg = FTP (watts) ÷ Weight (kg)
This is the single most important metric for climbing and overall cycling performance. Two riders with the same FTP will climb at very different speeds if their weights differ.
| W/kg | Level |
|---|---|
| < 2.0 | Beginner |
| 2.0 – 3.0 | Recreational |
| 3.0 – 3.5 | Sportive / Gran Fondo |
| 3.5 – 4.0 | Club racer |
| 4.0 – 5.0 | Amateur racer |
| > 5.0 | Elite / Professional |
VO₂ Max (estimated)
Maximal Oxygen Uptake — the maximum rate at which your body can consume oxygen during intense exercise, expressed in ml/kg/min.
VéloPeak estimates your VO₂ Max from FTP and weight using the Coggan formula:
VO₂ Max (est.) = (W/kg × 10.8) + 7
This is an estimate — a lab VO₂ Max test is more accurate — but it provides a useful benchmark to track progress over time.
| VO₂ Max | Level |
|---|---|
| < 35 | Beginner |
| 35 – 45 | Recreational |
| 45 – 55 | Trained |
| 55 – 65 | Well-trained |
| > 65 | Elite |
As your FTP improves relative to your weight, your estimated VO₂ Max will rise.
TSS (week)
Weekly Training Stress Score — the sum of TSS from all activities in the last 7 days.
This gives you a quick view of your current weekly training load:
| Weekly TSS | Typical volume |
|---|---|
| < 150 | Low (maintenance) |
| 150 – 300 | Moderate (base training) |
| 300 – 500 | High (structured build) |
| > 500 | Very high (race prep / overload) |
Use this alongside ATL and TSB to decide whether to add intensity or back off.
How VéloPeak calculates these values
- Every time you sync your Strava activities, VéloPeak calculates a TSS for each workout using your FTP and normalised power.
- Activities are grouped by day (multiple workouts on the same day are summed).
- The CTL and ATL exponential moving averages are computed across your full activity history.
- The result is stored as a daily snapshot and shown on your dashboard.
- W/kg and VO₂ Max are derived in real-time from your profile FTP and weight.
The more history you have synced, the more accurate the numbers will be.
Tips
- Before a race: aim for TSB between +5 and +20 — fit but fresh.
- After a big week: a TSB of -20 to -30 is normal. Don't panic.
- Grow CTL slowly: 3–5 points per week max to avoid injury.
- Track W/kg over months: a rising W/kg (without gaining weight) confirms real fitness gains.
- VO₂ Max plateaus: once you're above 50, gains come from consistency and high-intensity work over years, not weeks.