Bonjour Remi
Il y a beaucoup de questions dans ton message 
Q1. Can i compare workouts or activities? YES. simply ask “compare workouts on 18th January and 3rd January” (add year if different).
for example for me:
Here’s a side-by-side comparison of your two key training days — 3rd January vs 18th January 2026 — both of which featured long, demanding Alpe du Zwift sessions:
Workout Comparison
Attribute 3rd Jan 2026 18th Jan 2026
Difference / Interpretation
Session Name Zwift – Alpe ×2 (smoked by Smash Magnus) Zwift – Alpe ×2 Same route; different load quality
Type Virtual Ride Virtual Ride —
Duration 2 h 30 min (9005 s) 2 h 22 min (8509 s) ~8 min shorter
Distance 55.4 km 54.6 km Essentially identical
TSS (Training Load) 144 144 Equal workload
Intensity Factor (IF) 0.758 0.781 +3% higher on 18 Jan — slightly more intense
Average HR 128 bpm 121 bpm -7 bpm → better cardiovascular efficiency
ICU Intensity 75.8 78.1 Slightly higher — confirms marginally harder pacing
Power Distribution (assumed) Even Z2–Z3 focus Slightly higher Z3 proportion 18 Jan likely had shorter recoveries or more constant effort
VO₂max Context Stable (68) Stable (68) Aerobic efficiency unchanged
Fatigue Phase End of Build block Mid-Recovery block Same TSS produced less fatigue load → good adaptation
Interpretation
On 3 Jan, the Alpe x2 session represented a peak-load endurance challenge, done near the end of a build phase.
HR drift and intensity suggest moderate aerobic strain with fatigue accumulation.
Efficiency lower (higher HR at same IF).
On 18 Jan, the same TSS was achieved with lower HR, slightly higher IF, and shorter duration — a hallmark of improved aerobic durability.
You produced equal load with less cardiac cost.
Indicates recovery adaptations and better pacing control.
The metabolic efficiency (FatOx 0.68) and MES (22.5) metrics confirm this trend.
Coach’s Summary
Efficiency gain: 7 bpm lower HR at same workload → improved aerobic conditioning.
Load tolerance stable: both sessions = 144 TSS → durability sustained post-deload.
Pacing refinement: shorter, slightly more intense effort on 18 Jan with equal physiological cost.
Recommendation:
Use future Alpe repeats as controlled benchmarks — maintain HR <125 bpm at ~0.78 IF.
If HR <120 bpm next session for same TSS, consider increasing FTP or extending climb time by +10%.
Bottom Line:
Your 18th January Alpe x2 was more efficient, better recovered, and demonstrated clear endurance gains since 3rd January.
then ask to “analyse the intervals within each workout”, it will give you a greater amount of detail for both. you can also compare, highlight what worked what didnt etc..