A weightlifter should strive to be in the optimal weight category for their body to be able to perform the best they can. It can certainly be the difference between a podium finish and a mid-field finish.
The body weight category that an athlete competes in will largely depend on their current body weight and body fat levels. The lifter will want to have as much muscle on their frame as they can to enhance their strength potential while being relatively lean to increase power output.
The Body in Space
Many studies have shown that in sports where the body moves through space, as in weightlifting, a higher percentage of body fat has been shown to decrease athletic performance.
One of these studies tested young men with different levels of body fat on a number of performance tests to determine the relationship of body fat with performance. The figure below shows the results of these performance tests—specifically looking at the standing long jump which is an assessment of power output.
The table below shows that there is decrease of performance in relation to high body fat levels. It is not unreasonable to assume that power output increases the leaner the athlete is. One reason for this is that muscle is metabolically active—it can contract to produce force whereas body fat is inactive and its primary use is to store energy.
The less body fat an athlete has, the less force is needed to move inactive body mass through space. Although performance can be hindered if this is taken too far and body fat levels are taken to unhealthy levels.
|Tests/Measurement||Performance Test Results|
|Body Fat Percent||Low (<10%)||Moderate (10-15%)||High (>15%)|
|75 Yard Dash||9.8||10.1||10.7|
|220 Yard Dash||29.3||31.6||35.0|
|Standing Long Jump||23.8||22.7||20.2|
The effect of relative body fat on select performance tests in young men (sum of three trials). Adapted from Riendeau, et al (1958).1
Body fat can be easily measured and, from this information along with weight, a coach/athlete can calculate what weight an athlete can safely achieve. Body fat can be indirectly measured through a skinfold caliper, which measures skinfold fat thickness at multiple sites in which the value obtained can be used to estimate relative body fat.
Once the body fat percentage has been determined then the weight of fat-free mass (muscle, bone, organs) can be calculated in order to determine what an athlete should weigh at a specific body fat percentage. An example is given below with the calculations used.
|Body Fat Percentage||18%|
|Fat Weight||14.4kg (weight x 18 %)|
|Fat-Free Weight||65.6kg (weight – fat weight)|
|Body Fat Percentage Goal||12% (= 88% fat-free)|
|Weight Goal||74.5kg (fat-free weight / 88%)|
|Weight Loss Goal||5.5kg (weight – weight goal)|
How to Drop Body Weight
Reducing body weight is a process that has three different components; the weight lost mainly through reduction of body fat, weight lost through glycogen depletion, and weight lost through water lost through perspiration. Most of the weight should be lost through reduction of body fat and glycogen stores in the body.
This can be done by gentle dieting with the aim of reducing food quantity to elicit a small calorie reduction but not so much that it leaves the athlete hungry throughout the day. Junk food should be eliminated or at least minimalized during this period.
Only a small calorie deficit should be done so that it does not affect the athlete’s strength or performance levels. The athlete should aim to be no more than 3% over body weight a week before competition.
In the last week before competition, protein and fat sources like chicken, beef, eggs, and nuts should be favored over carbohydrate sources. Also, a conscious effort should be taken to increase water intake in order to encourage perspiration due to the hormone changes that decrease water retention.
When carbohydrate foods are ingested by the body, the body breaks the food down to its basic components, one of which is glucose. Any glucose not used by the body is then transformed into glycogen to be stored in the liver and muscles, to be later transformed back into glucose for energy.
Since weightlifting primary uses the creatine phosphate energy system which is responsible for providing energy from the breakdown of creatine then the reduction of glycogen in the body will not affect weightlifting performance on single lifts but it may affect recovery between lifts.
Time for Competition
With the reduction of glycogen stores, the athlete will see a reduction in body weight due glycogen being attached to water molecules. Specifically for every 1g of glycogen stored, 3g of water is stored with it. It is not unusual for an athlete to lose 1-3kg through this process.
The athlete wants to be no more than 0.5kg overweight by the time they go to bed the night before the competition, in which case the remaining weight will be lost through water lost by perspiration.
On the morning of competition, after weigh in, the athlete should drink an isotonic solution like Powerade or Lucozade to replenish some of the glycogen stores. They should also eat some food that they are used to eating, preferably sources of protein and carbohydrates. This is to ensure good recovery between lifts.
1. Riendeau, R.P., Welch, B.E., Crisp, C.E., Crowley, L.V., Griffin, P.E., & Brockett, J.E. Relationships of body fat to motor fitness test scores. Research Quarterly. 1958, 29, 200-203.