Hydration
Whether it’s hot or cold on the day of the Tough Ruck, you will sweat a significant amount. Hydration is key to restocking the water and enabling you to continue. A good rule of thumb is to take a sip at least once every half mile, increasing your intake as the temperature rises or if you’re a heavy sweater. You will lose more time due to muscle cramps and dehydration than you will lose by stopping to drink at every opportunity.
Fuel
Unless you follow a ketogenic diet – and you’ll know if you do – your body uses glycogen as its main source of fuel. For the purposes of this guide, think of glycogen as carbohydrates. You’ll need to replace at least some of carbs you’re burning. But how many?
According to The Mayo Clinic, a 160-pound person burns 511 calories per hour backpacking and a 200-pound person burns 637 calories per hour backpacking. (Backpacking is a good approximation of rucking.) You won’t need to replace all those calories to get through the event but we recommend 100-300 calories per hour over the course of the ruck.
There are multiple sources you can choose from. Some people swear by energy gels or goo, protein bars, fruit, pizza, or even fried chicken. Any liquid calories you ingest count too, including soda or electrolyte drinks like Gatorade®.