So when I was in high school I could do a max of 25. 30 years later, I get a pull up bar for my kids. I do mini competitions with them. On the best day I could throw up 14 and I would literally feel like throwing up after the attempt. Despite doing indoor bouldering and occasional pull ups for a year, that max doesn't budge. I stop bouldering/pullups after getting a left frozen shoulder. COVID hits. I did PT home band exercises for 6 months. More importantly, I also pick up commute cycling(20 mi rt per day). Shoulder is better. Restarted pullups 4 months ago with 5-7 reps of 5-7 pullups. The interval is scattered throughout the day depending how busy it is at work. Last week I attempted a max. 22. I can see adding 2 maybe 3 to my previous max, but not 8. My conclusion is it has to be the biking.