Plan a Week of Varied Workouts Around a Single Constraint

Generic weekly workout plans assume you have standard time, equipment, and a body with no particular limitations. Most people do not. This designs a seven-day plan around the specific constraint that stops you using the standard advice, includes an active recovery day, and tells you what to watch for and what to adjust if the week is harder than expected.

I want to plan a week of workouts. My main constraint is: {MAIN_CONSTRAINT} [for example: I only have a 20-minute window each day, or I can only train at home with bodyweight, or I have a lower back injury].

Additional context:
- Current fitness level: {FITNESS_LEVEL}
- What I actually enjoy: {ENJOYABLE_ACTIVITIES}
- Goal for this week: {WEEKLY_GOAL}

Give me:
1. A seven-day schedule with one workout per day (including one rest or active recovery day), each described in [two to three sentences] including what it is, how long, and why it fits the constraint
2. One thing to watch for this week that would tell me the programme is working
3. One adjustment I should make if I am [significantly more tired than expected] by day four