Weather
Run in the Heat
When talking about running in heat, the first thing is obviously hydration, which we discuss in details here.
The less common topic is that you may want to adjust your target pace/effort according to the heat too.
Measurement
When measuring the impact of heat, temperature is obviously the first factor.
However, humidity is can have a far more impact sometime (e.g., when humidity is very high). It reduces the cooling effect of evaporation, which is how our body cool down via sweating.
One proxy we can use to combine the two factors above is
Dew Point is often accessible in weather report, which is
Below is the adjustment chart from Maximum Performance Running
Run in the Cold
Protection
Keeping the body warm from the cold is always the top priority. Weather can be unpredictable and poses risk to health and life.
Overall, similar to many other outdoor sports:
- Layers - so that you can adjust when necessary. Generally, one wants to dress 15-20 degrees warmer than the actual temperature. Also, also pay attention to wind, which can take away heat from the body easily.
- Hat - a hat is almost a necessity in winter.
- Gloves - do not be afraid to wear heavy gloves. One's hands/warms are less active, so sometimes heavy gloves (e.g. ski gloves) can be helpful.
- Masks/neck gaiters - less popular, but definitely helps a lot in extremely cold weather.
- Shoes - given one's feet are very active, they generally need less protection from the cold. However, many sole material can behave differently (stiff, grips), plus icy road increases the risk of slipping.
Safety
Daylight is much shorter in many places, so make yourself visible by wearing reflective, or flashing lights for safety. It is even helpful to bring a headlamp.
Hydration
Our body is often less sensitive to thirsty during cold weather. That does not mean it needs less. Still pay attention to hydration.
More Warm-Up
This one is probably obvious. Being cold outside, we will need more time to warm up.