reckonerIndoor bike
A stationary bike with a seat, pedals and a resistance you can turn up. It takes no skill to start, puts no impact through your joints, and is the easiest machine to keep at a steady effort, which is why it is the first machine Reckoner reaches for when it places cardio. Almost everything that goes wrong on it comes from a seat set at the wrong height.
- Measured
- Minutes
- Loading
- None
- Ways to use it
- Steady, intervals
- Counts toward
- No muscle's weekly sets
How to do it
Set the seat at hip height
Stand beside the bike and raise or lower the seat until it is level with the bony point at the side of your hip. That is a starting point, and the check from the saddle settles it. Lock the pin before you sit.
Check it from the saddle
Sit with the ball of your foot on the pedal and the pedal at its lowest point. Your knee should be a little bent, never locked straight. If your hips rock from side to side to reach the bottom, the seat is too high. If your knee is still well bent at the bottom, it is too low. Getting it right is worth a minute: in a lab study of recreational cyclists, the front of the thigh worked least at the middle of five seat heights, not the lowest or the highest2.
Set the handlebars where you can sit tall
Higher and closer is easier on your back and neck while you learn. Your elbows should be soft and your shoulders away from your ears.
Strap in and start light
Tighten the pedal straps over the ball of each foot, or clip in if the bike and your shoes allow. Start with the resistance low enough that the pedals turn easily.
Spin smoothly, then add resistance
Find a steady turn of the pedals, push through the ball of the foot, and keep your knees tracking in line with your feet. Add resistance a little at a time until your breathing says you are working.
Let your breathing set the effort
For a steady ride you should be able to talk but not sing1. If you can only say a few words, you have moved into hard work.
The two ways
- Steady
- One effort the whole way, at a pace you could talk through. When Reckoner places a ride, it is this one, as a warm-up or a finisher.
- Intervals
- Harder spells with easy spells between, for example a minute hard and two minutes easy. They are harder work, and a choice you make: the plan never places them.
How to start easy
Five to ten minutes, light resistance, a spin you could keep up for an hour. Add a few minutes or a little resistance the next time, not both. The US physical activity guidelines put it as "start low and go slow"1. Leave intervals until steady riding feels routine.
What goes wrong
The seat too low
It is the most common setting in any gym, because the last rider was shorter. A low seat keeps your knees deeply bent all the way round, and in a study of 25 riders a lower seat left the hips and knees more bent and, in the researchers' model, put more load on the leg muscles and joints3. Set the seat every time you get on.
The seat too high
The opposite fault shows as hips rocking on the saddle and toes pointing down to reach the bottom of the stroke. Lower the seat until your hips stay still.
Too much resistance too soon
Grinding a heavy gear at a slow cadence turns a steady ride into leg work. Spin lighter and faster before you add weight to the flywheel.
Hunching over the bars
Rounding the back and dropping the head is how a twenty minute ride ends with a stiff neck. Sit tall, raise the bars if you need to, and keep your shoulders relaxed.
Questions people ask
Upright, recumbent or spin bike?
Any of them. They all count as the indoor bike. A recumbent bike supports your back, a spin bike lets you stand, and an upright bike sits between them. Set the seat the same way on each and ride at the same easy effort.
Is my watch's heart rate right on the bike?
It tends to be good here, because your wrist is still. In a lab test on a stationary bike, a Garmin Forerunner read, on average, within about 1.4 to 2.3 beats per minute of a hospital grade ECG4. Distance is another matter: your wrist measures no distance on an indoor bike.
Why does Reckoner reach for the bike first?
Because it is the easiest machine to start on and to keep steady. There is no balance to learn, no impact, and no technique that changes the effort, so an easy ride stays easy. When Reckoner places cardio, the bike is the first machine it tries.
Does Reckoner count this toward my lifting?
No. Reckoner counts cardio toward no muscle's weekly sets, and your lifts stay as planned whichever way you ride.
Other machines
Sources
- Piercy, Troiano, Ballard and colleagues, JAMA, 2018. The Physical Activity Guidelines for Americans the talk test, the 0 to 10 effort scale, and "start low and go slow"
- Bing, Zhang, Wang and colleagues, BioMedical Engineering OnLine, 2024. Effects of workload and saddle height on muscle activation of the lower limb during cycling eighteen recreational cyclists at five saddle heights from 95 to 105% of greater trochanter height; front thigh (rectus femoris) activation was lowest at the middle height, 100%, which the authors judged probably the appropriate saddle height for most cyclists
- Bing, Chen, Zhang and colleagues, BMC Sports Science, Medicine and Rehabilitation, 2026. The effects of saddle height and power output on lower-limb muscles and joints during cycling twenty-five participants; a lower saddle left the hips and knees more flexed, and a musculoskeletal model driven by their motion and pedal forces estimated higher loads on lower limb muscles and joints
- Ho, Yang and Li, Digital Health, 2022. Accuracy of wrist-worn wearable devices for determining exercise intensity on an electronically braked cycle ergometer, a Garmin Forerunner 945 read heart rate with a mean absolute error of 1.35 to 2.25 beats per minute against a 12-lead ECG