Five weeks of structured training. Endurance work, VO2max intervals, Sweet Spot efforts, over-unders, and tempo progression. You’ve done the work. Now it’s time to see what that work has built. Meet the FTP Test – 20-Minute Protocol – the moment of truth.
This isn’t just another workout. It’s an assessment, a benchmark, a reality check on your fitness. The classic 20-minute FTP test is cycling’s gold standard for measuring sustainable power. And after five weeks of progressive training, you’re about to discover exactly how much faster you’ve become.
Why Test at All?
Here’s the thing about training zones: they’re only useful if they’re accurate. That FTP number you’ve been using to calculate all your intervals? It determines whether your Sweet Spot work is actually Sweet Spot, whether your tempo efforts are tempo, whether your threshold intervals are threshold.
Get your FTP wrong, and everything else falls apart. Set it too high, and you’re constantly failing workouts, accumulating fatigue, and wondering why training feels impossible. Set it too low, and you’re leaving gains on the table, doing workouts that don’t create enough stress to drive adaptation.
After five weeks of progressive training, your FTP has almost certainly changed. The question isn’t whether you should test – it’s how much have you improved. Testing gives you that answer and resets your training zones for the next block of work.
Plus, let’s be honest: there’s something deeply satisfying about seeing concrete evidence that all those early mornings and hard intervals actually made you faster. Numbers don’t lie.
The Classic 20-Minute Test
The 20-minute FTP test is the most widely used protocol in cycling for good reason: it’s simple, it’s proven, and when executed properly, it provides accurate results that you can trust for months of training.
The concept is straightforward: after proper warm-up, you ride as hard as you can sustain for exactly 20 minutes. Not “kinda hard” – as hard as you can maintain from start to finish. Your average power for those 20 minutes, multiplied by 0.95, gives you your estimated FTP.
Why 0.95? Because most riders can sustain slightly higher power for 20 minutes than they can for a full hour. The 5% reduction accounts for this difference, giving you a sustainable FTP estimate that translates accurately to training zones.
The challenge isn’t the protocol – it’s the execution. Twenty minutes of maximum sustainable effort requires precise pacing, serious mental toughness, and the willingness to truly suffer. Start too hard, you blow up. Start too conservatively, you underestimate your FTP. Finding that perfect balance where you finish completely empty but maintain power throughout? That’s the skill.
The Workout Breakdown
Total Time: 58 minutes
Intensity: 10/10 (during the test)
Training Stress Score (TSS): ~75
Structure:
- 15 minutes Progressive Warmup (45-85% FTP): Building gradually from easy to moderate intensity
- 3 minutes Pre-Test Activation (85-110% FTP): Short high-intensity bursts to activate your neuromuscular system
- 5 minutes Test Recovery (40-50% FTP): Active recovery to clear activation efforts
- 20 minutes FTP Test (95-105% FTP): All-out sustainable effort at threshold – this is the test
- 15 minutes Extended Recovery Cooldown (30-50% FTP): Gradual recovery after maximal effort
The test itself is those 20 minutes where everything matters. But the structure surrounding it – the progressive warmup, the activation bursts, the recovery before the test – all of that ensures you’re truly ready to give your best possible effort when the clock starts.
What makes the 20-minute protocol challenging is the pacing. You need to find a power you can hold for the full duration without cracking. Too aggressive in minutes 1-5, and you’ll pay dearly in minutes 15-20. Too conservative early, and you’ll finish with energy left, knowing you could have gone harder.
The pre-test activation bursts (3 minutes with efforts at 85-110% FTP) are crucial. They prime your neuromuscular system, elevate your heart rate closer to test levels, and essentially “wake up” your body so the test effort doesn’t come as a shock. Think of them as opening the throttle briefly before the main event.
How to Nail Your Test
Be rested. This is not negotiable. Testing when you’re tired from yesterday’s ride gives you garbage data. Take at least one full rest day before your test, preferably two if you’ve been training hard. You want to see your actual fitness, not your fatigued fitness.
Fuel properly. Eat a carb-focused meal 3-4 hours before your test. Your performance during a 20-minute test is highly dependent on having adequate glycogen stores. Don’t test fasted unless you want artificially depressed results.
Set up your cooling. You’re going to be at threshold for 20 minutes. Your body will produce massive amounts of heat. Without proper cooling, you’ll overheat and fail early. Point a strong fan directly at your torso. This is not optional – proper cooling can make a 10-20 watt difference in your result.
Execute the warmup properly. All 15 minutes, building progressively from 45% to 85% FTP. Your body needs this gradual preparation. Don’t skip it, don’t rush it. The activation bursts that follow are equally important – three minutes of varied intensity with some efforts above threshold wakes up your system.
Pace the test intelligently. Here’s the strategy most riders use successfully: Start at what feels like 95% of your target power. Hold that for 5 minutes. If you feel good, gradually increase to your target power. By minute 10, you should be at your actual threshold effort. Minutes 10-15, hold steady. Minutes 15-20, give everything you have left. The last 5 minutes should hurt more than anything that came before.
Don’t look at the clock constantly. Check at 5-minute intervals to ensure pacing is on track. But staring at the seconds ticking by will make the suffering feel endless. Focus on your breathing, your power target, your pedal stroke – anything except how much time remains.
Finish completely empty. If you have anything left in the final minute, you paced too conservatively. The last 3-5 minutes should be brutally hard, and the final minute should require every bit of mental toughness you possess. This is maximum sustained effort – you should cross the line with nothing left.
Use the full cooldown. Fifteen minutes of easy spinning after a maximal 20-minute effort isn’t excessive. Your body needs time to clear metabolic waste and begin recovery. Don’t just stop and get off the bike.
What Your Results Mean
After the test, your training software will likely calculate FTP automatically (average power x 0.95). Now what?
If your FTP increased: Congratulations. The training worked. Your zones will automatically adjust upward, making your future workouts appropriately harder to match your improved fitness. This is progress happening in real-time. Accept the new number and trust it.
If your FTP decreased: This happens less often, but it’s not automatically bad. Were you properly rested? Properly fueled? If not, retest when conditions are better. If you were rested and the number dropped, you might be overreaching – accumulated fatigue masking fitness gains. Consider a recovery week and retest.
If your FTP stayed the same: Also valid data. Maybe you’ve been maintaining rather than building. Maybe you’re in a plateau that needs different training stimulus. Maybe your FTP wasn’t set accurately before. Use this as your new accurate baseline.
The most important thing: accept the result. Don’t manually adjust your FTP because you “feel like it should be higher.” Don’t reject the test because the number surprised you. Your subsequent workouts will confirm whether the FTP is accurate. If Sweet Spot efforts suddenly feel like tempo, the number was probably low. If threshold work feels impossible, it was probably high. But start with the test result and adjust only if training confirms it’s off.
The Mental Game of Testing
The 20-minute FTP test is as much a psychological challenge as a physical one. The first 5 minutes feel manageable. Minutes 5-10 are where doubt creeps in – “Can I really hold this for another 10 minutes?” Minutes 10-15 require serious mental commitment – the suffering is real and there’s still significant time remaining.
Minutes 15-20 separate those who test well from those who don’t. This is where you discover your true mental toughness. Your body will scream. Your brain will negotiate. “Just back off 5 watts. No one will know.” “This is close enough.” “Good enough is good enough.”
Ignore every one of these thoughts. The test isn’t over until the clock hits 20:00. Every watt matters. Every second of maintaining power matters. This is your chance to see what you’re actually capable of when you refuse to quit.
Here’s a useful mental trick: break it into chunks. Can you hold this power for 5 more minutes? Yes? Then do it. When you hit 15 minutes, ask again: can you hold this for 5 more minutes? The answer is yes. When you hit 18 minutes, you know you can do 2 more. Anyone can do 2 minutes.
The final minute will test everything. Your legs will burn like never before. Your breathing will be desperate. Your heart rate will be maxed. And you’ll keep pedaling anyway because you know the end is seconds away. This is what maximum sustainable effort actually feels like.
After the Test: What’s Next
Immediately after you stop, spin easy for the full 15-minute cooldown. Your body just went through maximum sustained effort and needs time to clear metabolic waste. Don’t just stop and get off the bike.
You’ll likely feel surprisingly okay within 10-15 minutes of finishing. The 20-minute test, while brutally hard during execution, doesn’t create the deep neuromuscular fatigue of some other protocols. Most riders feel ready to train again within 24-36 hours, though taking a full day off or doing easy spinning is smart.
Update your FTP in whatever training platform you use. All your future workouts should be based on this new number. Those five weeks of training just paid off in measurable watts. Your Sweet Spot intervals will be slightly harder now. Your tempo work will be at a higher absolute power. That’s the point – you’re stronger, so the training adapts.
And most importantly: appreciate what the number represents. It’s not just watts. It’s early mornings when you didn’t feel like training but did it anyway. It’s intervals where you wanted to quit but finished strong. It’s consistency, discipline, and progressive overload paying dividends. That higher FTP? You earned every watt of it.
Getting Started This Week
Find the FTP Test – 20-Minute Protocol at velovostra.com/workouts.
Free download, same as always. Input your current FTP to get the proper warmup intensities, though the test itself is simply “go as hard as you can sustain for 20 minutes.” Compatible with all major training platforms.
Scheduling your test: Pick a day when you’re well-rested and have no time pressure. Morning tests often work well if you’re a morning person and properly fueled. Avoid testing after a hard training week. This needs fresh legs.
Environment matters: Most riders find indoor testing more accurate due to perfect power control and no variables (traffic, wind, terrain). But if you have a steady outdoor course (ideally a gradual climb), outdoor testing can work well too. Choose based on what allows you to execute best.
Your mission is simple: start pedaling at your target power and don’t stop until 20 minutes is complete. No strategy beyond intelligent pacing. No games. Just pure sustained effort until the clock runs out. The test will tell you exactly how fit you are right now.
Next Week’s Preview
You’ve tested. You know your new FTP. Your zones are reset. Now what? Time to put that fitness to use with a workout that teaches progressive intensity management across multiple zones. Get ready for pyramids.
Want Systematic Testing and Progression?
Individual tests like this one are valuable snapshots of your fitness. But real progress comes from structured training that builds systematically between tests, with each workout designed to push your FTP higher for the next assessment.
VeloVostra creates complete training plans that integrate testing strategically – building your fitness for 4-6 weeks, then testing to establish your new baseline, then building again from that higher starting point. It’s progressive overload done right, with every workout connected to the bigger picture.
Whether you’re training 3 hours per week or 12, whether you’re targeting events or personal bests, there’s a plan that eliminates guesswork and maximizes your return on training time.
How did your test go? Were you surprised by the result? Did five weeks of training pay off in watts? Let me know – and if you’re looking for what comes next after testing, check out the complete workout library to build on your new fitness baseline.
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