When bodybuilding, we all strive for the "pump". Even since Arnold compared it to sex in "Pumping Iron", physique athletes have used it to gauge the success of their workouts. I wanted to share my views on this because while a good pump during/after a workout is great, it isn't always a requirement for a good workout.
The "pump" occurs from two events - large amounts of glycogen stored in the muscle sales and increased blood flow to the muscle. When you eat a large amount of carbs and/or are getting sufficient carbs from your meal plan, your body converts them to glycogen and stores them in the liver and muscles. You body also adapts to weight training by increasing the number of capillaries feeding muscle tissue to aid growth and endurance. When you lift, the muscle becomes engorged with blood and is using the stored glycogen as fuel. What happens if you are lowering your carbs to lose body fat or following a Ketogenic diet where your body uses fat as it's key energy source? Well the growth in capillaries doesn't change but the pump does. You will experience little to no pump in this state as your body is primarily burning fat as fuel which is not stored locally in the muscle.
My point is, don't think that you must always have a pump to achieve muscle growth or signify a great workout. If you train properly and eat right, whether you are eating lots of carbs for size or cutting down on carbs to get lean, you are still causing micro-tears in the muscles and forcing them to adapt. The only time for concern is if you are eating and training to gain weight and you are not experiencing quality pumps. It either means you are not training the target muscle group correctly or you need some serious rest.
John
