By: Johan Svensson  | Date: 2006-08-31  | Category: Training    | (3) Comments



Edu Marin fights the pump on La Rambla, 9a+.
Picture Sam Bié.

Wouldn’t it be nice if pumped forearms did not exist? Athletics have been fighting with immediate muscle soreness (pump) for decades, but the only solution appears to be training, and proper eating and drinking. This article takes a look at the "pumped" syndrome, what is causing it is and how you can deal with it.


There are three main factors that interact to produce pumped forearms, 1) acidosis of muscle tissue (low pH), 2) spastic contraction of the muscles (i.e. cramp), and 3) reduced blood circulation through your muscles.

1) Contrary to common belief pump, i.e. immediate muscle soreness, is not caused by the accumulation of lactic acid, as lactic acid cannot be produced under regular circumstances in human tissues. Instead, a substance called L-lactate is constantly produced during normal metabolism and exercise. During intense exercise when the rate of demand for energy is high the rate of lactate production exceeds the rate of lactate removal. This is a beneficial process that ensures maintained energy production during the exercise. The acidosis that is associated with increases in lactate concentration during heavy exercise arises from a separate reaction. In brief this has to do with the increase of “loose” hydrogen ions during hydrolysation (cell respiration). During intense exercise, aerobic (oxygenic) metabolism cannot produce enough energy to supply the demands of the muscle. As a result, anaerobic (non-oxygenic) metabolism becomes the dominant energy-producing pathway. This leads to an overload of tissues with “loose” hydrogen ions, causing pH to fall and creating a state of acidosis. This contributes to the acute muscular discomfort experienced shortly after or during intense exercise.

2) Cramp has two main causes, 1) fatigue, and 2) low hydration. Fatigue (1) means that cramp sets in when our muscles are tired due to inadequate oxygenation (oxygen-flow). Resting, reloading of energy (i.e. eating) and stretching the muscles may solve this problem. Low hydration (2) means that there is a lack of water or salt in the cells, which reduces the functional ability of the muscle cells. Remember, cramp can also be an indication of low health condition, i.e. you are sick or not fit enough.

3) Reduced blood circulation and low oxygen levels can be caused by muscle-contraction-squeezing of the capillaries. In fact, heavy loads during long intervals may close the capillaries completely, resulting in acidosis and great pain. The same thing can occur when the arms get flooded with blood. This happens when the veins are unable to remove the surplus of blood that the arteries, which have a higher pressure, continually force into the arm. The overflow “squeezes” the capillaries, further lowering the ability to remove “old” oxygen-poor blood.

Note: Children have a higher ratio of capillaries to muscle fibre and a lower ability to contract their muscles, producing a more constant supply of blood to the muscles.


•    Warming up is essential if you want to reduce pump. A short walk, run or jumping up and down will increase your blood flow. Stretch some before climbing and start of with some easy routes or moves that will get your muscle activity going. Don’t chock your muscles.

•    Do not forget to eat and drink before, during and after climbing, as this will help you avoid cramp. The amounts of food and drink required vary and you will have to learn what is right for you and your body. In general, fast energy (i.e. sugars), minerals (i.e. salts) and water are most important during climbing, especially if conditions are warm and humid.

•    Gripping technique is important, since pump increases with high and constant load. Reducing the contact time between hand and hold by using a more pulsating gripping technique may help. Try to alternate the load between arms, rest the “loose” arm and breathe continually.

•    Improved foot technique, such as heal hooks and knee-drops, will enable you to put more load onto your feet and legs, saving some of the pressure and load on the arms.

•    Pump often occurs right after intense exercise (e.g. a crux move, long hard sequence, etc). To avoid spoiling you chances of another “go”, hold your hands above your head and gently squeeze the palm of your hands to increase blood-flow. Soft massage and stretching may also help, but don’t pound the muscles or over-stretch as this can increase the soreness!

•    Pump is also dependent on your general fitness. A healthy body has a lower risk of pump, although this is also genetically determined. Try to keep fit and don’t climb when you’re sick.