Ever wonder why you feel exhausted or outright pass out, after hitting the beach or just being out in the sun? Is it just you getting older or something else?
We’ve all had the experience of struggling to stay awake after a sudden rush of sun exposure in the summer. My kids seem to do it no problem, day after day but I’m ready to pass out and never wake up. What’s going on?
Internal Clock
Our biological clock uses light exposure as one of the important factors for regulating a sleep schedule. Light signals that it’s time to wake up and the lack of light signals bedtime. Sudden exposure to a large amount of sunlight may reset the clock, triggering sudden drowsiness once you get out of the beach.
Thermoregulation
The human body’s internal temperature is quite fragile and functions properly under rather strict ranges of temperatures. If your core temperature drops (hypothermia) or rises (hyperthermia) a few degrees, you could be in serious medical trouble. The human body has mechanisms to regulate the core temperature, like shivering, and sweating, but all this physiological effort consumes energy, leaving you feeling exhausted.
Dehydration
Spending time out in the sun can dehydrate you due to sweating, even if you’re not particularly active. Your body is losing both water and salt through sweat, leading to symptoms of mild to moderate dehydration-exhaustion and sleepiness.
Most people think of dehydration as equivalent to the sensation of thirst, but this is not accurate. By the time that you feel thirsty, your body is significantly dehydrated. The sensation of thirst also decreases with age, so it’s vital to be drinking water before you feel the thirst.
Oxidative Damage and Chemical Changes
The sun emits UV radiation which has a variety of harmful effects on people. The primary rays that penetrate the ozone layer are UVA and UVB light. When these rays hit the skin, it induces a cascade of chemical reactions in the body that taxes the body. These may be contributing factors to exhaustion.
The Takeaway
Exhausted after the beach or a picnic at the park? Lots of changes are happening in your body while you are being exposed to the sun, and if you aren’t used to it, the urge to pass out might be irresistible! These physiological reactions are natural, so there is no cause for alarm, but make sure that your skin is well protected with a broad-spectrum sunscreen.
