Structured Training Guide for Smart Trainers: Using Scientific Methods to Improve Your Riding Performance

The advent of smart trainers has completely transformed the landscape of indoor cycling training. From the monotonous days of staring at a wall while pedaling hard, to now being able to precisely control resistance, simulate real routes, and execute scientific training plans, smart trainers have made indoor training unprecedentedly efficient.

Getting to Know Your Smart Trainer

ERG Mode vs. SIM Mode

Smart trainers have two primary operating modes, and understanding the difference between them is the foundation of effective training:

ERG Mode (Constant Power Mode)

• The trainer automatically adjusts resistance to maintain a target power output
• Regardless of your gear ratio or cadence, your power output is locked to the target value
• Best suited for executing structured training plans
• Drawback: If cadence drops too low, you may fall into the “spiral of death”

SIM Mode (Simulation Mode)

• Simulates resistance changes of real terrain
• Resistance increases on climbs and decreases on descents
• Riding feel is closer to outdoor riding
• Suitable for free riding and virtual route experiences

The Importance of Power Accuracy

When choosing a trainer, power accuracy is one of the most important metrics. Power accuracy on mainstream smart trainers typically ranges from ±1% to ±3%. The higher the accuracy, the more reliable your training data, and the more precise your progress tracking.

Performing a Spindown calibration before each training session is the fundamental practice for maintaining accuracy:

1. Ride for 10 minutes to warm up the trainer
2. Execute the calibration procedure through the trainer’s app
3. Follow the instructions to accelerate to a specific speed, then stop pedaling
4. Wait for the trainer to complete the calibration

Building Your Training Foundation: FTP Testing

What is FTP?

FTP (Functional Threshold Power) is the maximum average power you can sustain for approximately one hour. All intensity zones in structured training are set based on FTP.

Common FTP Testing Methods

The 20-Minute Test

This is the most common FTP testing method:

1. 10-minute warm-up (gradually increasing to 65% of estimated FTP)
2. 3 × 1-minute high-cadence efforts (100+ rpm)
3. 5 minutes of easy recovery
4. 5-minute all-out sprint (to clear anaerobic energy reserves)
5. 10 minutes of easy recovery
6. 20-minute all-out time trial (this is the key part)
7. 10-minute cool-down

Multiply the average power of the 20-minute effort by 0.95 to estimate your FTP.

Ramp Test

A more time-efficient alternative:

• Start at a low power and increase by a fixed wattage each minute (usually 20W)
• Ride until you can no longer maintain the power
• Take 75% of the power from the last completed minute as your FTP
• Advantages: Less dependent on pacing ability, less painful
• Disadvantages: May overestimate FTP for riders with strong anaerobic capacity

Recommended Testing Frequency

• Retest every 6-8 weeks
• Test when transitioning between training blocks
• Test when you feel the training intensity no longer matches your current level

Training Zones: Seven Intensity Levels

Based on FTP, training intensity is divided into the following zones:

Zone	Name	FTP Percentage	Primary Benefit
Z1	Active Recovery	< 55%	Promotes recovery, warm-up and cool-down
Z2	Aerobic Endurance	56-75%	Builds aerobic base, fat metabolism
Z3	Tempo	76-90%	Improves aerobic efficiency, muscular endurance
Z4	Lactate Threshold	91-105%	Raises FTP, delays fatigue
Z5	VO2max	106-120%	Increases maximal oxygen uptake
Z6	Anaerobic Capacity	121-150%	Develops anaerobic power
Z7	Neuromuscular	> 150%	Maximal sprint power

Core Workout Types

1. Aerobic Endurance Training (Z2)

Purpose: Build the aerobic base, enhance fat metabolism

Warm-up: 10 minutes @ 50-60% FTP
Main set: 60-120 minutes @ 65-75% FTP
Cool-down: 10 minutes @ 50% FTP

This is the most fundamental and important training. Many riders overlook the value of long-duration, low-intensity training, but it is the foundation for all high-intensity work. In ERG mode, maintain a cadence of 85-95 rpm.

2. Sweet Spot Training

Purpose: Gain near-threshold training benefits at a lower fatigue cost

Warm-up: 15 minutes progressing to 70% FTP
Main set: 2-3 sets × 15-20 minutes @ 88-94% FTP
Rest between sets: 5 minutes @ 55% FTP
Cool-down: 10 minutes

Sweet Spot training is the best choice for time-constrained riders, as it effectively raises FTP without accumulating excessive fatigue.

3. Threshold Intervals

Purpose: Directly challenge and raise FTP

Warm-up: 15 minutes progressive
Main set: 3-4 sets × 8-12 minutes @ 95-105% FTP
Rest between sets: 5 minutes @ 50% FTP
Cool-down: 10 minutes

4. VO2max Intervals

Purpose: Increase maximal oxygen uptake, raise the aerobic ceiling

Warm-up: 15 minutes progressive
Main set: 5-8 sets × 3-5 minutes @ 106-120% FTP
Rest between sets: 3-5 minutes @ 50% FTP
Cool-down: 10 minutes

This is the most painful but also the most breakthrough-inducing training. It is recommended to maintain a cadence of 95-105 rpm.

5. Sprint Workouts

Purpose: Develop short-duration explosive power and neuromuscular recruitment

Warm-up: 20 minutes progressive (including 3 short sprint activations)
Main set: 8-10 sets × 15-30 seconds all-out sprints
Rest between sets: 3-5 minutes easy spinning
Cool-down: 10 minutes

Note: Sprint workouts are recommended to be performed in SIM mode or Level mode, as ERG mode’s response speed is insufficient to handle instantaneous power changes.

Periodized Training Planning

Base Period (4-6 weeks)

Focus on aerobic endurance and Sweet Spot training:

• 3-5 training sessions per week
• 70% Z2 aerobic endurance
• 20% Sweet Spot
• 10% skill drills (high cadence, single-leg pedaling)

Build Period (4-6 weeks)

Gradually introduce high-intensity training:

• 4-5 training sessions per week
• 40% Z2 aerobic endurance
• 30% threshold intervals
• 20% VO2max intervals
• 10% recovery rides

Peak Period (2-3 weeks)

High intensity with reduced training volume:

• 3-4 training sessions per week
• Training volume reduced by 30-40%
• Intensity maintained or slightly increased
• Include race simulation workouts

Recovery Period (1-2 weeks)

• Training volume and intensity significantly reduced
• Focus on easy riding
• Allow the body to fully recover and prepare for the next training cycle

Common ERG Mode Pitfalls

Spiral of Death

When your cadence begins to drop in ERG mode, the trainer increases resistance to maintain power, which makes it harder for you to pedal, causing cadence to drop further, creating a vicious cycle.

Prevention methods:

• Maintain a steady cadence, do not let it drop below 75 rpm
• If you feel you can’t turn the pedals, actively shift to an easier gear to raise cadence
• Pause the workout or lower the target power if necessary

Over-Reliance on ERG Mode

Long-term exclusive use of ERG mode may cause you to lose the ability to self-regulate power output. It is recommended to use SIM mode or free riding at least once a week to practice feeling and controlling your power output.

Conclusion

Structured training is the most effective way to improve your riding ability, and smart trainers provide the perfect tool for executing this training. The key lies in: accurately measuring your FTP, choosing appropriate training plans based on your goals, following periodization principles, and consistently tracking your progress. Remember, training quality always matters more than quantity, and adequate recovery and consistency are the true foundations of long-term progress.

Related Reading

• The Physics of Smart Trainers: Differences Between Flywheel Inertia, Grade Simulation, and Power Matching Modes
• Indoor Trainer Power Training: Correct Use of ERG Mode and Common Pitfalls
• ERG Mode vs SIM Mode: A Decision Tree for the Two Smart Trainer Modes
• Indoor Trainer Interval Training: Differences Between ERG Mode and Resistance Mode