Most people trying to get fit fall into one of two camps:
- Camp 1: Endless treadmill jogging in the “fat-burning zone”
- Camp 2: Random HIIT classes where you collapse in a pool of sweat, unsure if you’re actually improving
Neither is ideal. One is boring and time-consuming. The other is chaotic and hard to measure.
If your goal is to build real fitness, improve cardiovascular health, and increase VO2 max — without wasting hours or wrecking your joints — there’s a smarter way:
✅ Use data.
✅ Use structure.
✅ Use the Assault Bike.
In this guide, you’ll learn:
- Exactly how to test your fitness using a 1.5-mile Assault Bike test
- The data you need to collect: RPM, heart rate, recovery heart rate
- How to calculate your Maximum Aerobic Speed (MAS)
- A progressive training plan based on science, not guesswork
- Why this method is safer and more effective than pounding the pavement
🚴 Why the Assault Bike is the Smarter Tool for Cardio
Let’s be honest — running is great, but it’s not always joint-friendly.
Every foot strike on a treadmill can deliver 2–5x your bodyweight through the knees. If you’re overweight, deconditioned, or carrying old injuries, running may set you back more than it helps.
The Assault Bike, however:
- Has zero impact
- Uses both upper and lower body
- Provides instant feedback (RPM, watts, HR)
- Works across all energy systems
It’s the perfect tool to test and train aerobic fitness in a safe and measurable way.
🧪 Step 1: The 1.5-Mile Assault Bike Test
This test is the foundation of your program.
It’s not random. It’s not a sprint.
It’s designed to reveal your Maximum Aerobic Speed (MAS) — the lowest effort level where your body hits peak oxygen usage (VO2 max).
🧭 What to Do:
- Warm up for 5–8 minutes at a moderate pace.
- Reset the bike to 0.00 miles.
- Ride as fast as possible for 1.5 miles.
- Track:
- Time
- Average RPM
- Average watts
- Max heart rate at the end
- Heart rate at 60s and 120s post-finish
🧮 What to Record:
| Metric | Why It Matters |
|---|---|
| Time | Total time gives context for endurance level |
| Average RPM | This becomes your MAS baseline |
| Watts | Another way to set and progress intervals |
| Max HR | Used for future recovery benchmarks |
| HR @ 60s/2min | Measures how well you’re recovering (fitness marker) |
💓 How to Use Heart Rate Recovery (HRR) as a Fitness Marker
Beyond just testing your speed and power, the real gold is in how quickly your heart recovers after a hard effort.
That’s where Heart Rate Recovery (HRR) comes in — a proven marker of cardiovascular fitness, recovery ability, and even long-term heart health.
After your 1.5-mile test, and after each interval in training, you should measure your heart rate at:
- 60 seconds after stopping
- 120 seconds after stopping
🎯 Your HR Recovery Targets:
| Time After Stopping | Ideal Drop | Why It Matters |
|---|---|---|
| 60 seconds | Drop of ≥30 BPM | Shows good parasympathetic (rest-and-digest) response |
| 120 seconds | Drop of ≥50 BPM | Indicates strong cardiovascular fitness and recovery ability |
💓 Example: Meet Sarah
Let’s say Sarah completes her 1.5-mile test in 5:45 at 60 RPM average, with:
- Max HR: 170 BPM
- HR after 60s: 145 BPM
- HR after 2 mins: 128 BPM
This gives her:
- MAS = 60 RPM
- Target 60% HR = 102 BPM
- She’s recovering well (drops of 25–42 BPM in 2 minutes)
🧪 Example HR Recovery targets (from Sarah):
- Max HR at end of test: 170 BPM
- Goal HR @ 60s: ≤140 BPM
- Goal HR @ 120s: ≤120 BPM
If you’re not hitting these numbers yet — don’t worry. It gives you a clear target to improve over time. As your aerobic base and VO2 max improve, these recovery numbers will too.
This becomes a simple, repeatable way to track progress without needing fancy equipment.
🔬 Why This Works: The Science of MAS
Maximum Aerobic Speed is the threshold where your body is working at full oxygen capacity, but not yet relying heavily on anaerobic systems.
Training at or just above MAS:
- Improves your VO2 max (the engine size of your aerobic system)
- Builds fatigue resistance
- Helps you recover faster between efforts
- Makes all other forms of training feel easier
📈 Step 2: Build Intervals Based on MAS
Now that you know your MAS (in RPM), you can build a structured conditioning plan that is:
- Measurable
- Progressive
- Joint-friendly
- Repeatable
Here’s how to program it:
🎯 Target Heart Rate-Based Recovery
After each interval:
- Rest until your HR drops to 60% of your test max (e.g., 60% of 170 BPM = 102 BPM)
- This ensures aerobic recovery, not anaerobic crash
📏 Interval Rules
- Start with 3 intervals
- Intervals = 15–30 seconds at 100–110% MAS
- e.g., if MAS = 60 RPM, ride intervals at 65–70 RPM
- Rest = until HR returns to 60% of max (use a heart rate monitor — ideally wrist or chest strap)
- Monitor HR after each interval:
- If HR spikes more than +6 BPM between intervals (e.g., 150 → 156 → 170), you’re going too fast
- Scale back to stay aerobic
📆 Weekly Progression
- Aim to increase total interval volume by ~10% per week
- Going from 3 to 4 intervals is a 25% jump — that’s okay in the early weeks
- Track recovery HR too — it should get faster over time
📋 Sample Week-by-Week Plan
| Week | Intervals | RPM Target | Rest Condition | Notes |
|---|---|---|---|---|
| 1 | 3 × 15s | 65 RPM | HR < 60% max | Learn pacing |
| 2 | 4 × 15s | 65 RPM | HR < 60% max | Small jump |
| 3 | 4 × 20s | 65 RPM | HR < 60% max | Extend effort |
| 4 | 5 × 20s | 65–70 RPM | HR < 60% max | Harder, stay controlled |
| 5 | Re-test MAS | — | — | Re-calculate based on new fitness |
📉 How You Know You’re Improving
- Average RPM or watts increases for same heart rate
- Recovery HR drops faster after intervals
- You can handle more volume without HR spikes
- Your resting HR lowers
- Strength workouts feel easier
👊 Final Thoughts: No More Random HIIT
Too many people jump into bootcamp-style cardio, chasing calorie burns without building any real engine.
This plan flips that on its head:
- Grounded in data
- Structured around your fitness level
- Focused on longevity and performance, not punishment
And because it’s done on a bike, it’s easier on your joints and scalable to any level.
🛠️ Summary Checklist
✅ Complete a 1.5-mile Assault Bike test
✅ Record: time, average RPM, max HR, 60s HR, 2-min HR
✅ Calculate MAS (average RPM)
✅ Use MAS to set interval targets (100–110% MAS)
✅ Use HR to guide rest (recover to 60% of max)
✅ Progress weekly by 10%
✅ Re-test every 6–8 weeks