Yeah, once your only going 110 mph on a bicycle, the danger is pretty much over. /s
I suppose the athlete would need to wear an EVA suit (or a diving suit? the requirements are sort of between the two), so that'd be a bit of a damper on their peak performance, but still.
Of course, that sounds more like a skill involving reduction of friction and outputting as much power through the legs as possible than the more difficult act of also controlling a bike at those speeds.
With rollers (what I'd think the "treadmill" discussed above actually is), and a normal road bicycle, you can feel, or at least hear, the resistance just from the spokes in a spoked wheel when you really get get them spinning "real world" fast.
On fancier road race wheels, the spokes are "bladed" for this reason - their cross section is flattened to minimise aerodynamic drag. Remember that when you're riding a bike in normal conditions, the top of the wheel is hitting the oncoming air at up to twice the speed of the bike. Though, there's also a substantial amount of appearance/marketing/armchair-engineering around...
Even amateur cyclists often use "aero wheels" that no longer have spokes. They make a difference in the wind or at 20mph.
I don't think this is feasible with today's wind tunnels, though.
Plus it will save your nose. My cousin was in a bad high speed motorcycle accident and cracked his helmet. Slid a long way.. He lost a lot of skin on his toes, ended up having fused vertebrae, but his face was ok.
She said her thoat was covered in salt by the end of this high speed ride. needed a respirator.