Disclaimer: I like going to the gym and strength training so there is that aspect of whether it improves cycling performance.
I have found that strength training either on the bike or in the gym can provide added value increasing performance. The challenge for me is having enough energy and recovery to work it in to a training plan. If I lift in the gym at a hard enough level to be material to my cycling, I am tired on the bike. So if I want to improve road performance then I do leg strength training from October to January or some variation of that period.
If I am training more for track then I extend the time period. I can always do maintenance upper body and core work year round. My bread and butter leg strength exercises are deadlift, hip thrust, single leg seated press, Roman chair isometric hold and box jump. On the bike they are seated and standing starts and 100 meter jumps.
IMO, glute work may be the most important work that we cyclists do in the gym since strong functional glutes are necessary to protect our back. That is according to one of the physical therapy sponsors that supported one of the racing clubs I used to belong to. They also recommended the Roman chair iso hold for cyclist to strengthen the lower back / glute neuro connection and align the vertebrae.
I have a bad back and glute thrusts do not hurt my back where as deads and back lifts and other exercises that load up the vertebrae can. When I do deads, it is all about form and not weight and I use the trap bar and bend my knees more. The deads and the hip thrust are the most technical so it is good to have a trainer watch ones form from time to time.
It is easy for cyclists to get injured in the gym since we are like special snowflakes so keep that in mind when starting any strength program - less is more and form is everything.
Last edited by Hermes; 09-06-19 at 07:19 AM.