Fifty degrees is the hardest layering call in running. Too much and you cook. Too little and you spend the first two miles miserable.
My 50°F system
Short-sleeve tech tee. Light long-sleeve merino over it. Running shorts or light tights. Wind layer in a waist belt, optional. That's it.
The long-sleeve merino is the key piece. I push the sleeves up by mile two and roll them down if it gets cloudy or breezy. It breathes enough that I don't overheat, and it's warm enough at the start that I don't dread the first half mile.
What not to wear
A full fleece. Too warm by mile one. You'll tie it around your waist for the rest of the run and hate yourself.
Cotton anything. Even at 50°F, cotton gets damp and stays damp, and then the temperature perception is off.
A rain shell preemptively. If it's not raining, it's a windbreaker at best and a sauna at worst. Carry it, don't wear it.
What about 45°F?
Add a buff and gloves. Keep everything else the same. Extremities get cold faster than torsos in chilly running weather.
What about 55°F?
Swap the merino long sleeve for a short sleeve and just run in the tee. Some people will argue with me here. I'm a warm runner. Cold runners stay in long sleeves until 60.
Know yourself
Are you a warm runner or a cold runner? Run a 5K easy and check your armpits after mile one. Soaked means warm runner. Dry means cold runner. Pick your layering baseline from there and adjust up or down 5 degrees.
Come by the Memphis store and try the merino long-sleeves. Smartwool and Icebreaker both work. Fit is what separates them.
