Calories

What Does Calories Do?

Calories represent the fundamental unit of energy your body utilizes to power through every rep, set, and sprint. While many modern pre-workouts are calorie-free, those that include them are designed to provide immediate substrate for ATP production and muscle contraction during high-intensity training.

• Immediate Fuel Source: Provides the raw energy needed for high-intensity muscle contractions and sustained power output.
• Glycogen Sparing: Consuming calories, particularly from carbohydrates, helps preserve your stored muscle glycogen for the most demanding parts of your session.
• Enhanced Endurance: Maintains blood glucose levels, which prevents the 'bonking' effect or sudden fatigue during long-duration or high-volume training.
• Anti-Catabolic Effect: By providing an external energy source, you reduce the likelihood of the body breaking down muscle tissue for fuel during intense exertion.

Clinical vs. Gym Bro Dosing

Key Insight: There is no universal clinical dose for calories in a pre-workout; your intake should be dictated by your total daily macronutrient targets and whether your specific training style requires a fed state for peak performance.

Side Effects & Warnings

• Gastrointestinal Distress: Consuming too many calories too close to a workout can lead to bloating, nausea, or cramping as blood is diverted from the gut to the working muscles.
• Reactive Hypoglycemia: High-sugar calorie sources can cause a rapid insulin spike followed by an energy 'crash' if the workout doesn't begin shortly after ingestion.
• Unintended Weight Gain: If you do not track the liquid calories in your pre-workout, they can easily push you out of a caloric deficit or maintenance phase.

Tip: If you choose a caloric pre-workout, look for sources like highly branched cyclic dextrin which exit the stomach quickly to minimize the risk of a 'heavy' stomach during your sets.