The pump is caused by blood rushing into the muscle faster than the circulatory system can remove it. Many bodybuilders assess the quality of their workout by the level of pump. If the worked muscle does not pump to any degree, the individual often feels the workout was wasted. The level of pump varies among individuals and also within one individual. You may get an incredible pump from one set on one day, while on another day no amount of exercise will bring on the desired feeling. In addition, it’s possible to fully pump the muscle only to lose the pump with continued exercise. When you begin to lose the pump, stop exercising that particular muscle.
The idea is to become so in tune with your body that you know exactly the maximum number of sets to perform without losing the pump. Is a good pump necessary? Although it’s not a prerequisite for growth, the general consensus is that the better the pump, the greater the development. A good pump signifies that the muscle in question is receiving a good blood supply. Also, the speed at which a muscle pumps up is indicative of its neuromuscular pathway. There is a definite relationship among supply, nerve transmission and muscle growth. In short, the better the blood supply to a muscle, the better it pumps, and the faster it grows.
The important aspect is not so much the blood but rather what it carries. As the body’s chief transport medium, blood brings to the muscles all the nutrients and oxygen needed for growth and repair. At the same time blood removes such metabolic wastes as carbon dioxide and lactic acid. An increased blood supply also means the establishment of more blood vessels.
If you need more convincing, ask yourself this question: “What are my best bodyparts?” Chances are your best muscle groups are those that pump up the fastest and to the greatest extent. On the flipside of the coin, those muscles that lag behind probably pump up little or not at all. Achieving a proper pump requires intense, heavy training, not endless sets of reps using light weight.
Such training strategies as Vince Gironda’s 6 sets of 6 reps with 30 seconds rest between sets, and Dorian Yates’ high-intensity training (a modification of Mike Mentzer’sheavy-duty system) are great ways to achieve the maximum pump in the shortest time. What happens if you fail to achieve a pump or it’s much smaller than usual? Such a failure is caused by one of several factors. All the training in the world will not produce a pump if there is no glycogen in your muscles. A flat look to the muscles and a failure to achieve a pump are caused by insufficient glycogen storage. You need more carbs such as sweet potatoes and oatmeal.
Another reason for a less-than-adequate pump is overtraining. Doing 20 or 30 sets per bodypart is the surest way to hold yourself back and in many cases reverse your progress. There is no way your recovery system can restock the body’s muscles with glycogen if you follow such a routine. Why do sprinters have huge muscular thighs while marathon runnershave long slender thighs? Sprinters concentrate on doing the maximum amount of work in the shortest time. Marathon runners, on the other hand, expend so much energy over such a longtime that their systems (particularly their muscles) never get a chance to totally recover.
The same principle holds true for bodybuilders. Spend hours on the stationary bike or performing endless high-rep sets, and the muscles cannot help but take on a stringy appearance. There is a fine line between not enough and too much. If you’re eating properly and not over training, the lack of a pump is due to some other cause. How long do you rest between sets? Anything over two minutes is way too much. Most bodybuilders find 45 seconds to a minute to be the best rest interval.
If you can operate on less rest – say, 30 seconds or so – you most certainly will achieve a pump, as long as you’re getting 6 reps per set. Other training techniques that almost guarantee a pump are supersets, trisets and giant sets. All of these training practices ensure much work being done in a short time – the perfect conditions for a great pump. While achieving a pump is not an absolute necessity, it is one of the most frequently used benchmarks for measuring the adequacy of a workout. Make a habit of leaving the gym with a muscle-busting pump, and there can be but one outcome – growth.
Robert Kennedy: Encyclopedia of Bodybuilding, The Complete A-Z Book On Muscle Building. 2008
Nick Evans: Bodybuilding Anatomy. 2012
Arnold Schwarzenegger: The New Encyclopedia of Modern Bodybuilding, 2013