The Definition and Classifications of Strength
Translated from "China Weightlifting Textbook" by Sean GU July 08 2020
The Definition and Classifications of Strength
LU doing snatch pull
DStrength and Weightlifting cannot be separated. Strength is of utmost importance for a weightlifter and is the foundation for their success.
The Definition of Strength
Strength is a manifestation of human movement. It is the ability of a human’s muscles to counteract against gravity when the muscle fibers contract and relax. A muscle must overcome both inner and outer resistance when it is working. Outer resistance includes the weight of the organism, friction, and air resistance. Inner resistance includes the stickiness of muscles and the forces the muscles have against each other. Strength generation is based on three factors: how much the active muscle is contracting, the combined workings of an active muscle with the antagonist muscle, neutral muscles, and support muscles; the angle in which a muscle is working and the length of the drag and power arm in the lever system.
Strength comes from muscles. 43.5 percent of a normal adult male’s bodyweight will be muscle. This number is 35 percent for adult females. An active male will have an increased percentage of 45 percent. An athlete that competes in strength sports can go beyond 46 percent.
Scientific research has proven that the human body has 630 individual muscles. These muscles are formed by thirteen to thirty million muscle fibers. Every muscle fiber can counteract 100 to 200 milligrams of weight. If we take all 630 muscles, morph them into one, and have them produce force in one direction, the resulting force could counteract 20-30 tons. A male’s strength levels can achieve the following numbers: a 216kg snatch, a 266kg clean and jerk, a 550kg squat, a 2840kg rack hold.
A female can snatch 151kg and clean and jerk 188kg. At the beginning of the 20th century, circus strongwomen Sandvina from Belgium could carry a 600kg cannon from a cart. On March 9, 1994, an Australian strongman was able to drag a 115 ton Boeing 747 over a distance of 61.81meters.
The Classification of Strength
Strength in sports, depending on requirement and how it is displayed, can be classified into different categories. For example, depending on how much a muscle contracts, strength can be split into static and dynamic strength. To relate bodyweight and strength, there are the topics of absolute strength and relative strength. Depending on how strength is displayed, it can be categorized as absolute strength, speed strength, or strength endurance (Figure 3-1).
Figure 3-1 Strengths classification
Static strength is the strength displayed to hold a specific position during muscular contraction. It is also termed isometric strength. An example is the strength used to support or balance an object.
Dynamic strength is the strength displayed to cause movement in the body or to move an object. It is also termed isotonic strength.
Dynamic strength includes absolute strength, relative strength, speed strength, maximum strength, and strength endurance.
Absolute strength is the ability of the body or a specific body part to overcome the largest resistance without taking into account the bodyweight of the athlete. From the perspective of a hard training athlete, the increase in absolute strength will go hand in hand with an increase in bodyweight. The development of absolute strength is very important for throwing events (shot put) and weight class events like weightlifting and wrestling. Weightlifting and shot put both require a high level of absolute strength. For example, American shot put athlete Woods (with a performance of 22.2 meters) has the following strength numbers: a 230kg bench press; a 300kg squat; and a 180kg power clean. From practice, if a male shot put athlete wants to surpass 20 meters, he must bench press 200kg or more.
Relative strength is the amount of strength displayed per kilogram of bodyweight. Its main use is to determine the relationship between an athlete’s absolute strength and their bodyweight. This measurement takes into account both absolute strength and bodyweight.
Relative strength = Absolute Strength/ Bodyweight
If absolute strength does not change or decreases, but bodyweight increases, then relative strength decreases. This is a disadvantage in weight class sports. Experience proves that gymnastics must have a relative strength ratio at least 1 in order to perform an iron cross. In other words, an athlete’s absolute strength must be able to counteract their own bodyweight. Soviet high jumper Valeriy Brumel had the highest relative strength of soviet jumpers from the 1960s. His ratio was 2.21 (His max back squat was 174kg and his vertical jump was 104 cm). We can see that relative strength is very important in many sports. Chart 3-1 shows 56kg, 69kg, 85kg, and +105kg weightlifting world records and the relative strength of the athletes.
Sheet 3-1 4 Weight classes Word Record holders’ relative strength ratio comparaison
Ref. Weight class Record holder WR Relative strength ratio
1 56 Halil Mutlu( Turkey ) 168 3.00
2 69 ZHANG Guozheng(China) 197.5 2.87
3 85 ZHANG Yong(China) 218 2.56
4 105+ Rezazadeh (Iran) 263 2.50
From examining the different weight classes as weightlifting developed, we see that relative strength decreases as bodyweight increases. In weightlifting, the athlete with the highest relative strength ratio is Suleymanoglu from Turkey (Figure 3-2). At the 1988 Olympics in Seoul, he broke the world records six times in the 60kg class. His total was 342.5kg (152.5kg + 190kg). Measuring his relative strength with his clean and jerk, we get 3.17. He has the highest ratio in the sport of weightlifting.
Maximum strength is the peak limit of force production displayed by the muscular contraction of an athlete. This is primarily based on the cross sectional area of a muscle, the distribution of the muscle fibers, and neurological excitability. These factors influence how much force can be produced when a muscle group or groups work. At the same time, the maximum force production can also change based on the angle the working muscle group is in. The maximum strength of an athlete is not unchanging. In fact, it is changing constantly. This means that an athlete should constantly test what their limit is. Maximum strength can be determined by an athlete’s one rep max.
The weigthlifter having the highest relative strength: Suleymanoglu Naim
Speed strength is how fast an athlete can perform a certain movement under certain conditions. This type of speed usually involves activating muscle groups in a short time frame (typically less than 150 milliseconds). In reality, training speed strength is training to perform certain movements faster.
The most typical manifestation of speed strength is explosivity. Explosivity is the maximum acceleration that can be achieved to overcome an opposing force in a short period of time. Explosivity is the combination of maximum strength and maximum speed strength. Its formula is:
Explosivity = Force * Speed
It can also be written as:
Explosivity = (Force * Distance)/Time
Explosivity can be displayed when lifting a weight overhead, throwing an object, or while moving the body. How much explosivity is determined by the combination of force and speed. Let's take a long jump athlete for example. Their starting strength is force produced in the shortest amount of time possible. This force propels the body. Speed strength can also be described by the following formula:
In the formula: Iis speed strength; F is the force produced by muscle contraction; t is the time it took for the muscle to contract
Explosivity requires that an athlete’s initial speed cannot be smaller than zero. This means that the muscle is already in a contracted state. Examples are the acceleration phase in sprinting, high jumps, and long jumps. In events like shot put, weightlifting, and wrestling, explosivity is very important. In addition, starting strength and reactive strength (including from bouncing and hitting) are also components that make up speed strength.
Strength endurance is how long an athlete can endure or how many reps they can perform while they are under an opposing force.
By taking into account different principles, we can classify strength into these categories. The most important dynamic strength metrics in sports are maximal strength, speed strength, and endurance. Thus, training dynamic strength mainly focuses on training maximal strength, speed strength, and endurance.