Hydration & Nutrition Tips for Physically Demanding Jobs

Whether you're a firefighter on a 16-hour shift or a construction worker grinding through a hot summer day, physically demanding occupations (PDO) push your body to the limit. These roles require strength, focus, endurance - and a lot of energy. The problem? Many workers don’t get enough fuel or fluids to match what their bodies are burning through.

Studies show that jobs like firefighting, agriculture, construction, and military service can cause daily energy expenditures exceeding 3,000 to 7,000 calories. At the same time, workers often experience intense heat, heavy sweating, and mental fatigue. Without the right hydration and nutrition strategy, all of this can lead to serious performance drops and health risks.

Energy Needs for Physically Demanding Jobs vs. Desk Jobs

The average desk worker burns around 70 calories per hour. In contrast, those in physically demanding jobs can expend over 300 calories per hour. Here’s what the research says about specific roles:

• Military: Daily energy needs can reach 7,000 kcal for special forces and field units.

• Firefighting: Shifts of 12+ hours lead to energy expenditures of up to 6,000 kcal/day.

• Construction: Tasks require high energy output comparable to ice skating or light weightlifting.

• Agriculture: Energy use can hit 3,400 kcal/day, especially in hot climates.

Despite these demands, some workers may only be eating half the calories they actually need. That kind of energy gap can sap endurance, impair focus, and even affect bone health and immune function.

Dangers of Starting the Workday Dehydrated

Heat stress is a serious risk in these environments, and it’s often made worse by dehydration. Workers in outdoor, high-intensity roles can sweat over a liter per hour - sometimes much more. Yet many arrive to their shift already in a dehydrated state. For example, Over 50% of agricultural and outdoor workers showed signs of dehydration before their workday began.

Why Does this matter?

• Dehydration over 2% body mass loss can impair physical performance and cognitive function.

• In hot conditions, fluid needs may exceed 1 liter per hour just to stay hydrated.

Drinking water throughout the shift is essential, but so is hydrating before and after work. The National Institute for Occupational Safety and Health (NIOSH) recommends one cup (8 oz) of water every 15–20 minutes, with electrolyte drinks recommended for work in the heat lasting more than two hours.

 The National Institute for Occupational Safety and Health (NIOSH) recommends one cup (8 oz) of water every 15–20 minutes, though fluid needs vary based on heat, work intensity, and individual factors; electrolyte drinks are advised for heat exposure over two hours.

Carbohydrates & Protein for Physically Demanding Jobs

Calories are the energy your body uses to power movement, muscle rebuilding, and brain function. And for jobs that combine endurance and strength, carbohydrates and protein are key.

• Carbs fuel long days. Workers should aim for 4–12 grams of carbohydrates per kilogram of body weight, depending on task intensity and duration.

• Protein rebuilds and preserves muscle. A daily intake of 1.4–2.0 g/kg of body weight can help support muscle maintenance , especially when under high physical stress or during caloric deficits.

Many workers may need to double their current food intake just to meet daily energy demands. Lightweight, portable, and high-energy snacks like dried fruit, crackers, and sport foods are easy ways to fuel up on the go.

Best Hydration Options for Hot & Physically Demanding Work

Water works great for many situations but in high-heat environments or long-duration shifts, electrolyte drinks can offer more  They help replenish sodium, potassium, and other minerals lost in sweat, while also improving fluid absorption.

Gatorade, for example, contains a balance of electrolytes and carbohydrates, making it a helpful hydration option during extended periods of physical labor or heat exposure.

Hydration & Nutrition Tips for Physically Demanding Jobs

• Start your day hydrated - don't wait until you’re already sweating

• Hydration needs vary per worker and per situation

• 8-10 oz. is the recommended amount for every 15-20 minutes in the heat

• Use electrolyte drinks for hot conditions or shifts over 2 hours

• Fuel with carbs during your shift - aim for 30–60 grams per hour

• Include protein throughout the day to support muscle recovery

• Choose non-perishable, portable, high-calorie snacks

Research Gaps in Hydration and Nutrition for Hard Labor Jobs

Most of what we know about hydration and nutrition needs comes from military and firefighter research. But other occupations - like manufacturing, agriculture, and construction - need more attention.

There’s also a big gap in pre-shift hydration education. Many workers don’t know they’re starting their day behind, which puts them at higher risk for heat illness, poor job performance, and even injury.

How Gatorade Helps

When you're putting in long hours in hot, physically intense conditions, hydration has to work harder than just quenching thirst. That’s where a product like Gatorade can help. Formulated with electrolytes like sodium and potassium, Gatorade helps replace the minerals lost in sweat. Plus, its carbohydrate content can help maintain energy levels during extended shifts, especially when you’re working in the heat for more than two hours.

For workers who need to stay alert, energized, and hydrated all day long, drinks like Gatorade can be a smart, convenient option to support overall performance and recovery.