Even without a dedicated power meter you can use your turbo trainer for measured and reliable power workouts. Here’s how…
‘P’ is for power…
With the increasing availability of power meters and power measuring turbo trainers, training with power is now more accessible. It all starts with your Functional Threshold Power (FTP) — the ‘steady state output you can hold for 60 minutes’.
This gives a performance point from which you can work out other parameters. For most, FTP equates to 25-mile time trial power. Your hypothetical 10-mile TT power (20 minutes) will be about 95 percent of FTP, and VO2 max (six mins) around 90 percent of FTP. These will help you set future training intensities.
But what if you don’t have a power measuring device? You can use your turbo speed to work out the same performance parameters and your interval intensities. You can call this FTP too if you like: Functional Threshold Performance.
Record heart rate for cross-referencing, but don’t use it as a training metric. Power and speed are the ‘anchored’ metrics. Repeatable performance measures need to be consistent, accurate and comparable — watts and kilometres are always the same. You can’t brag about heart rate zones to your mates.
Measure your FT power
Set your turbo to a ‘flat road’ slope, or resistance. Then ensure tyre pressure (100psi), roller resistance and warm-up procedure are recorded and set for this and all future tests. Consistency is vital.
Once fully warmed up, hit record on your turbo, or measuring device, then bring yourself to a steady-state, 10-mile TT pace and hold for 20 minutes.
If you crash at 19:30 you went too hard. If you can get to 20:30 you haven’t gone hard enough. At the end, record your distance, power, heart rate, average speed. You now have a benchmark for your indoor cycling performance.
Training with your new FTP
Now you have a metric for your six, 20 and 60-minute efforts, you can use the power or speed ratios to target your training intervals.
For example: use the classic two x 20-minute (five-minute recovery) FTP sessions at 85 percent of your 60-minute power/speed. For VO2 max sessions, ride five x 5-minute (3-minute recovery) intervals at 90–95 percent of your 6-minute power/speed. For three weeks, do FTP on Tuesday, VO2 max on Thursday, then in the fourth week, when rested, run another 20-minute test to measure improvement and reset targets.