Training Load
Training load: the math behind peak performance.
Every breakthrough and every injury share the same root cause: how you manage load. Too little and you stagnate. Too much too soon and you break down. Gneta tracks acute load, chronic load, and their ratio so you can push hard without pushing past the edge.
What You See in Gneta
Acute vs Chronic Training Load
Your acute training load (ATL) captures the fatigue from the past 7 days. Your chronic training load (CTL) reflects fitness built over 42 days. Gneta plots both on a single chart so you can see exactly when short-term fatigue is outpacing long-term fitness, the leading indicator of breakdown.
Training Stress Balance (TSB)
TSB is the difference between your fitness (CTL) and fatigue (ATL). A positive TSB means you are fresh, ideal for racing or hard sessions. A deeply negative TSB means accumulated fatigue. Gneta tracks your TSB daily so you can time your taper and arrive at race day between +10 and +25, the optimal freshness window.
Load Ratio with Safe Zones
The acute-to-chronic workload ratio (ACWR) is the single best predictor of injury risk. Gneta calculates your ratio daily and colour-codes it: green for the 0.8–1.3 sweet spot, amber when you drift toward 1.3–1.5, and red above 1.5 where research shows injury risk increases 2–5x. Stay in the green and you build fitness safely.
AI Coach Load Alerts
When your load ratio spikes above 1.5 or your TSB drops below -30, Gneta's AI coach flags it with a specific, data-backed warning. It reads your recent training pattern, recovery metrics, and sleep data to recommend whether to back off, substitute an easy session, or take a rest day, before your body forces one on you.
Free for all Garmin watches
The Science of Training Load
The Performance Management Chart (PMC) is the gold standard for tracking training stress. Developed by Andrew Coggan and Hunter Allen for cycling power data, its principles apply to every endurance sport. The model distils your training into three numbers: fitness, fatigue, and form.
Chronic Training Load (CTL) is your fitness. It is an exponentially weighted moving average of your daily training load over the past 42 days. A higher CTL means a larger aerobic engine, but it takes weeks of consistent training to move. Think of it as your training bank account balance.
Acute Training Load (ATL) is your fatigue. It uses the same formula but over just 7 days, so it responds quickly to training spikes. After a hard training camp, your ATL might jump from 80 to 130 while your CTL barely moves. That gap is exactly what causes overuse injuries.
Training Stress Balance (TSB = CTL - ATL) is your form. A TSB of zero means your fatigue matches your fitness, a balanced state. Professional cyclists typically race with a TSB between +10 and +25. Elite marathon runners taper to reach a TSB of +15 to +20 on race day. Going above +30 often means you have rested too long and lost race sharpness.
The acute-to-chronic workload ratio (ACWR) distils this into a single number. Research by Tim Gabbett across rugby, cricket, and Australian football found that athletes with an ACWR above 1.5 are 2–5 times more likely to sustain a non-contact soft-tissue injury. Subsequent studies in running and cycling have confirmed the pattern. The 0.8–1.3 range, sometimes called the training sweet spot, allows progressive overload without dangerous spikes.
Gneta calculates all of these metrics automatically from your Garmin data. No spreadsheets, no manual logging. Your ATL, CTL, TSB, and ACWR update after every synced activity.
Frequently asked questions
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