Great question Mack. I will be honest, I don’t personally love 1x/week because — as discussed on the TR podcast from this week — at that rate each time you lift will be a novel stimulus for your body, and DOMS will start to become a bit more of a factor. Not to mention whether or not 1x/week is actually effective in developing strength given each person’s current baseline.
As noted far too many times than people probably would like (haha!), when it comes to frequency, it depends…
First deciding factor is what you are actually capable of sustaining. During 2020, I did 3x 2-3 hour rides per week and rested from the bike in between. I also lifted 4x/week — but I was working entirely remotely. My baseline for strength-training was really high, and my work schedule was 100% flexible, so it worked for me. I really did not see too much of a reduction in strength from my pre-structured riding days at that point.
But, as I wanted to invest more time into my riding and I went back to working 100% in person again, I had to increase the riding frequency to be able to make it fit in my schedule; between work, the dog, and life overall, I just don’t have more than 60-90 minutes at any given time to invest into training. So, when I wanted to do 6 hours on the bike per week with a normal working schedule, I had to do 4-6 rides of 60-90 mins per week, and therefore could only really manage 3 lifts per week at 45-60 mins per.
Fast-forward to now: I want to invest 8-12 hours per week on the bike, so I have needed to peel back to 2 lifts per week due to time constraints, and those have now dwindled down to just 30-45 mins per bout at most because I physically can’t handle much more. I just get the ’meat and potatoes’ knocked over and call it a day (i.e. my power and strength stimulus are prioritized, and the fluff is removed).
Next you have to factor in your baseline. If you are doing 0-1x/week in the weight room/gym, 2 sessions per week is plenty enough jump to see improvement, especially if you work to incrementally progress the workload within those sessions (intensity or volume) over the long haul. If however, like me, you are going from 4x/week to 3, to 2, well… you can’t expect to maintain the same level of strength. But that is the cost of focusing on other, somewhat conflicting physiological adaptations (those that we chase in our intervals and long rides). But, the beauty is that the sport’s demands dictate what is important: I may not be able to RDL 350 lbs or bench press 275 lbs (at 150 lbs BW) anymore, but marginal improvements in strength probably yield even more marginal gains in cycling performance since the sport does not directly demand strength in the same sense that we train in the weight room. Now, if you are an O-Lineman in American Football, a Shot-Putter, etc, you may want to think hard about when and how much strength you are willing to lose at any given time during the year.
It is a lot like the discussions on the amount of hours per week spent on the bike: a 10+ hour week sounds nice, but it just isn’t for everyone (for both lifestyle and athletic reasons). Ultimately, striving for a schedule and physical workload that you can tolerate, while conservatively striving to develop your strength is (in my semi-experiential opinion [I work with team-based, power-sport athletes, not endurance athletes]) is probably the safest bet.
Hope this long-winded answer helps some!
And for what it is worth, here is a blog post I wrote on my site diving into strength-training frequency as relates to cycling! The 4 Pillars of Strength-Training for Cyclists – Part I: Frequency