/seconded.
Sleeves should not just be on your vinyl collection, Hipsters.
Be proud of your tanlines!
For a more serious opinion - I don't generally wear a tshirt with a shorter sleeve than my cycling tops so doesn't cause me an issue. The only sleeveless things in any of my wardrobes are 'summer base layers' for cycling! To be honest Zwifting in this weather I don't bother with a jersey,
just one of these wide mesh types.
Think this is the current version (but I wouldn't pay more than £20/25 for one). I have actually found they keep me cooler than without - less channelling of sweat. So the increase in airflow (running 4 fans in summer - 1 of them a KICKR Headwind), seems to cause more evaporation (I'm maybe less aero, so more wind is caught against my torso?) so I'm less 'soaked' than riding without a base layer. I did short hill climb efforts (maybe only 90%) on KOM's as part of a race series last night in a 26 degree (ambient was 28) garage. Also wearing the same base layers outside when the afternoons are like this (25+).
If you’ve made it to the Red Line zone, with heart rates from 90% to 100% of your maximum heart rate, you have arrived at the top of the heap.
www.heartzones.com
You shouldn't be able to hit your Zone5 in anything than an absolute max effort. To stay there for that period of time would either imply you are incredibly VO2Max adapted (should be a Pro velodrome endurance/sprint rider), suffering from some kind of heart defect, had a faulty HRM, or just plain don't have your HR zones setup correctly (I hope it's the last one).
This is me doing a 'max HR' type Z5 ride - returning from Holiday, elevated HR due to no riding for 20 days and then riding at power levels I was doing before the break. Basically bouncing around my 'blow up territory' (over 180bpm) with my max HR being set as 190bpm (which I hit and hadn't hit for several years).