I was curious about this so I tested it myself. I used my AI prompt generator with the primary question “Increase my load this month by 10% and show me a projection graph” and sent that to Opus 4.6 with all my data from intervals.icu from the last 30 days. It came to 12,413 input tokens and 1,312 output tokens for a total cost of $0.09. EDIT: That would be ~$0.05 for sonnet 4.6 which seams to be the highest most expensive model any of these AI coaches are using in case anyone was wondering.
Below is my prompt (with my data stripped) and Opus’s response. Now this was run in a terminal so bless its heart it tried to draw the graph in ASCII, but given a proper environment where it could render JSX it would produce a much better visualization.
MY PROMPT:
The athlete’s primary question is: [Increase my load this month by 10% and show me projection graph.]. Anchor your analysis to answering this directly before covering broader trends.
AI Training Analysis Request
Role
You are a coach focused on endurance health, performance, and durability.
- Tone: direct and practical
- Response depth: concise
Context
- Goal type: Training analysis & feedback
- Sports emphasis: Run
- Date window: 2026-02-08 to 2026-03-10 (last 30 days)
How to approach this session
- Provide a practical analysis with clear next steps.
Term Definitions
- Load: Session training stress score (higher means harder overall workload).
- IF (Intensity Factor): Relative intensity vs threshold (1.00 = threshold effort).
- CTL (Chronic Training Load): Longer-term fitness trend from sustained load.
- ATL (Acute Training Load): Short-term fatigue trend from recent load.
- TSB (Training Stress Balance): CTL minus ATL; negative is higher fatigue, positive is fresher.
- For TSB/Form interpretation, use these Intervals.icu zones:
- Transition: > +20%
- Fresh: +5% to +20%
- Grey Zone: -10% to +5%
- Optimal (green): -30% to -10%
- High Risk (red): < -30%
- Cadence: Step rate (run) or pedal rate (ride), typically in steps or rpm.
- HRV: Heart rate variability, a recovery/readiness proxy.
- Resting HR: Baseline morning heart rate trend for stress/recovery context.
- NP (Normalized Power): Power estimate reflecting variable-intensity physiological cost.
- FTP/LTHR: Sustainable threshold markers used to set training zones.
Data Handling
- The data below is provided as CSV blocks. Use it as source of truth.
- If any zone setting data is missing or incomplete, do not guess or estimate HR, pace, or power zones.
- Call out missing or conflicting data before recommendations.
Response Format
- Return the response in Markdown.
- Use clear section headings and bullets.
OPUS REPONSE:
Load Increase Analysis & Projection
Direct Answer: Can You Increase Load by 10% This Month?
Not recommended right now. Here’s why, and what a safer path looks like.
Current Baseline
| Metric | Value |
|---|---|
| Recent 4-week avg weekly load | ~352 (weeks of Feb 9–Mar 8) |
| Current CTL | 32.9 |
| Current ATL | 47.9 |
| Current TSB | -15.0 (Optimal zone, but trending deep) |
| TSB low point | -18.2 (Mar 2) → touched near High Risk |
A straight 10% bump would target ~387/week → ~1,548 over 4 weeks.
The Problem
Several recovery signals are flashing amber/red:
- HRV dropped sharply: 7-day avg 96.4 vs prior 102.3 (−5.9), with today’s reading at 68 — your lowest in the entire window.
- Sleep collapsed: 7-day avg 5.7 hrs vs prior 7.1 hrs (−1.4 hrs). Last two nights: 2.55 and 5.45 hrs.
- Resting HR creeping up: 45.4 vs 44.6 (+0.8 bpm).
- Weight loss is aggressive: −0.42 kg/wk — fine if intentional, but combined with poor sleep this signals under-recovery.
- Long run concentration is extreme: ~80% of weekly km in a single session (week of Mar 2). This spikes injury risk.
Pushing load +10% on top of these signals is a recipe for illness or injury.
Projected Weekly Load: 10% Increase vs Recommended Path
Below is a text-based projection for the next 4 weeks (Mar 11 – Apr 7). The baseline uses your recent 4-week average of ~352/week.
Weekly Load Projection (Mar 11 → Apr 7)
────────────────────────────────────────────────────────────
Load
420 │ ╭── 10% Target (387)
400 │ ╭────╯
380 │ ╭────╯
360 │───────────── Baseline ────────╭────╯
│ (352) ╭────╯
340 │ ╭────╯
│ ╭────╯
320 │───── Rec. ─────╯ ╭── Recommended (370)
│ (317) (328) (345) (356) (363) (370)╯
300 │
└────────┬────────┬────────┬────────┬────────┬──
Wk1 Wk2 Wk3 Wk4 Wk5+
Mar 11 Mar 18 Mar 25 Apr 1
── 10% Jump Load: 352 → 387 immediately
── Recommended Load: 317 → 370 (graduated ~5%/wk)
| Week | 10% Target | Recommended | Notes |
|---|---|---|---|
| Wk 1 (Mar 11) | 387 | 317 (−10%) | Recovery/deload — fix sleep & HRV first |
| Wk 2 (Mar 18) | 387 | 345 (baseline) | Return to normal if HRV >95 & sleep >6.5 hrs |
| Wk 3 (Mar 25) | 387 | 363 (+5%) | First true overreach week |
| Wk 4 (Apr 1) | 387 | 370 (+5%) | Consolidate; reassess for another bump |
| Wk 5+ | 387 | 387 (+10%) | Reach your 10% target with a solid base |
Projected CTL at +10% (immediate): ~36–37 by Apr 7, but TSB likely dips below −25 (High Risk territory).
Projected CTL (recommended path): ~35–36 by Apr 7, TSB stays in Optimal (−10 to −20).
What to Fix Before Adding Load
- Sleep is the #1 priority. Your last 7-day average of 5.7 hrs is insufficient for adaptation. Target ≥7 hrs. No load increase will produce fitness gains on this sleep.
- Distribute long run volume. Cap your long run at ≤60% of weekly km. Add a mid-week medium run (8–10 km) instead.
- Monitor HRV daily. If 7-day HRV avg returns above 100 and sleep stabilizes above 6.5 hrs for a full week, begin the graduated increase in Wk 2.
- Weight loss pace is fine if deliberate, but don’t stack caloric deficit + load increase + sleep debt simultaneously.
Bottom Line
You’ll reach your 10% target load by week 5 (mid-April) using a graduated approach, arriving there healthy and adapted rather than overtrained. The immediate jump is high-risk given your current recovery state. Fix sleep first, deload this week, then build.
END PROMPT
Before anyone comments asking if I am ok. I am sick and also on vacation sking everyday and sleeping in a hotel so yes but in a good way.