Practical Tests for Measuring Muscular Strength Only a few tests of strength that are practical in terms of time, equipment, and cost are presented here. When special testing instruments are necessary for these tests, the cost is unreasonable for most schools. Tests are grouped under the headings "Isotonic Strength Tests," "Spring Scale Strength Tests," and "Isometric Strength Tests."
Evaluating Your Isotonic Strength The objective of isotonic strength tests is to measure strength through a complete range of movement. There are a number of valid methods for evaluating muscular strength; however, all of these methods require some type of equipment. Perhaps the most commonly used method is to determine your 1-RM. This is accomplished by finding the maximum amount of weight you can lift in a particular exercise. For example, if you are doing a bench press, you first warm-up with a weight you can easily handle for 8-10 repetitions. Rest for approximately five minutes, and then do another warm-up set with a weight you can easily lift for 5 repetitions. After these initial warm-up sets, load the bar to approximately 70 percent of what you believe to be the maximum amount of weight you can bench press, and do three repetitions. Rest approximately 5 minutes, and load the bar to 85% of what you believe to be the maximum weight you can lift. Do one repetition. After resting for approximately 5 minutes, do one repetition with the bar loaded at 95% maximum, and finally make your attempt at 100%. Do I need to say, “Don’t try more than 100%”? Okay, don’t try more than 100%. Here is something else you need to consider when evaluating your strength. As mentioned, there is no single test that correlates very highly with total body strength. This is probably due to the fact that strength is body specific. Therefore, in order to measure total body strength, each muscle group would have to be tested independently. To do this, you first find an exercise in which the muscle you want to test is the prime mover, and then simply determine your 1-RM in that exercise. As noted, the most common exercises used for evaluating strength are the bench press, squat, deadlift, and pull downs. The scores on these four lifts are generally considered a predictor of total body strength.
Resting Between Sets Although many teachers and coaches pay little attention to their rest periods between sets, they are of paramount importance. When a muscle is stressed to near maximum exertion and not given an opportunity to recover, it will fatigue. In turn, fatigue will reduce strength by decreasing the force and extent of muscle contraction. This decrease in the contractile power of the muscle is brought about in two ways. First, fatigue restricts the muscle from bringing into play all of its contractible fibers. Second, it decreases the contractibility or force of contraction of the muscle fibers that are involved. For the above reasons, it is important that you determine how much rest your muscles need between sets. Actually, there are a number of important factors to consider before reaching a decision as to how long you should rest between sets. One factor is the restoration of energy to the muscle. Now, this is going to be a little technical, but nothing you can’t handle. No!..No!...don’t turn the page…it’s not that bad. I promise. Besides, it’s important information. So, take your time and pay attention. The immediate source of energy for every movement an athlete performs comes from the breakdown of the chemical compound adenosine tri-phosphate (ATP). This substance is stored within
the cells of the muscles. As it is broken down energy is released, but only to a certain extent. This is because there is only so much ATP to be broken down. The only way the muscles can continue to perform their work is through resynthesis of ATP and the restoration of it to the depleted areas. This also requires energy. Our bodies have three ways of resynthesizing ATP and making it available to the muscles. In weightlifting and other short term, high-intensity bouts of exercise, the body utilizes the phosphagen (ATP-PC) system. In this system, the energy needed comes from the breakdown of phosphocreatine (PC), hence, the name ATP-PC system. Studies have shown that most of the ATP and PC stores depleted in the muscles during exercise are restored in what we could consider to be a relatively short period of time. For example, many studies show that after two minutes, 70% to 80% of the ATP has been resynthesized and that figure rises to 90% to 95% after four minutes. This would indicate that the rest taken prior to a top set, or a very important set, should be approximately four to five minutes in duration. Interestingly, rest periods longer than 5 minutes do not significantly enhance strength scores and in fact rest periods of 8 to 10 minutes may even bring about decrements in skill. Now, was that so bad? Don’t answer that.
Absolute and Relative Strength Here is something that might interest you. A couple of months ago Richard Simmons and Oprah stopped by my office. They were having this big argument. You know how celebrities are…just like the rest of us, only more so. Anyway, Richard said that his chest was stronger than Oprah’s. Of course, Oprah didn’t agree. She was positive her chest was stronger (remember though, big is not always better). As you have probably guessed they wanted me to determine who was right. Actually, that was no problem. I knew that the muscles primarily used to perform a bench press are the pectoralis major and minor…the chest. So I simply determined Richard’s and Oprah’s 1-RM in that exercise. Richard did a solid 1-RM with 100 pounds. Very impressive! Oprah though, surprised everyone by pumping out 120 pounds for her 1-RM. When Oprah made that lift she let out a scream…the kind that would scare Stephen King. She was so excited! But did this mean that Oprah’s chest was stronger than Richard’s chest? Watch out here this is a trick question. The answer is yes and no. You see there are two types of strength, absolute and relative. Absolute strength can be defined as the most weight you can lift (1-RM) regardless of your body weight. Relative strength can be defined as the most weight you can lift relative to your body weight. For example, let’s say we have two lifters; one weighs 150 lbs and the other weighs 200 lbs. Suppose the 150 lb. lifter’s 1-RM in the bench press is 300 lbs while the 200 lb. lifter’s 1-RM in the bench press is 310 lbs. In this instance, the lifter who weighs 200 lbs. is said to have greater absolute strength (in this exercise) because he lifted more weight, but the 150 lb. lifter is said to have greater relative strength because he lifted more weight per body pound. The 150 lb. lifter lifted twice his body weight, while the 200 lb. lifter lifted approximately 1 1/2 times his body weight. The question is, which is more important…relative or absolute strength? Watch out this is another trick question! Actually, it depends on the activity you are engaging in. If you were being tested for physical fitness, relative strength would obviously be preferred. However, if you were participating in a competitive sport where there are no weight classifications (such as football, track and field, or sumo wrestling) then absolute strength would be more important.
Here is something else you need to understand…generally speaking bigger individuals have greater absolutely strength and smaller people possess greater relative strength. This is especially true of highly trained or world class athletes. However, there are a number of formulas that can be used to calibrate for size difference. The Schwartz formula and the Malone formula are the two best formulas available. Both of these formulas can be found at in Appendix G. See, I always have your back. Okay, now let’s look at some of the test that could be used to evaluate isotonic strength.
Evaluating Your Isotonic Muscular Strength Squats Objective: to measure the strength of the quadriceps, hamstrings, gluteus maximum and minus and rhomboids…the primary muscle being the quadriceps. Age level: age 16 through college level. Reliability: Reliability coefficients range from .84 to .96. Objectivity: An objectivity coefficient of .97 was reported by Reico (1992). Validity: Face validity is generally accepted for this test. The test correlates .87 with total body strength when it is used to evaluate elite athletes. (Cotton, Biasiotto, and Chissom 1974) Equipment: Squat rack, Olympic bar, collar and free weights. Directions: I have already given you a pretty good analysis of the squat so this is going to be a little redundant…I will be brief. Although squatting form and efficient biomechanics is an individual matter, there are some principles that can be universally applied to every lifter. Unrack the weight with the bar positioned across the top of your scapula. When you are in position to "set up" with the weight place your feet so that they are three inches beyond shoulder width. When descending with the weight, try to keep your back in an upright position. It's important to keep your calves straight and your knees directly over your feet. Try to keep the weight back over your heels, aligning your position so that your power is centered vertically: It's also a good idea to point your toes slightly outward. This will allow you to lift the weight further back over your heels. It will also help you to flare your knees outward at the bottom of the lift. As soon as you break reach the bottom of the lift (for safety reason it is best to squat above parallel…at least 2 inches above parallel) tilt your back slightly forward, thereby bringing your hips into play to lead your ascent. As you drive the weight upward, gradually drive your thighs
inward and upward. This will help you to channel your power vertically. When you reach your sticking point, drive your shoulders backward and your hips inward until you are in an upright position. Try not to lean forward. If you do you will use a lot of back when squatting with free weight. That’s not good, because it will take stress off the quads and place it on your lower back. Additional considerations: Once again it can be seen that skill level is extremely important to performance…a major disadvantage in testing. In testing I would suggest that the subject’s depth should be no lower than two inches above parallel. As previously mentioned, when you go below parallel you use your lower back to get out of the bottom of the lift…that can be very dangerous. By having you subjects squat above parallel you are eliminating a lot of lower back involvement and decrease the risk of injury. Still, a 1-RM squat for an unskilled lifter can be dangerous.
Bench Press Objective: to measure the strength of the pectoralis major and minor, the triceps and the anterior deltoids. Age level: age 16 through college level. Reliability: Reliability coefficients range from .89 to .96. Objectivity: An objectivity coefficient of .95 was reported by Biasiotto (2004). Validity: Face validity is generally accepted for this test. Equipment: A bench, Olympic bar, collar and free weights. Directions: To perform a bench press, lie in a supine position (on your back) on a flat bench with your legs positioned at the side of the bench and your feet flat on the floor. Next, grip the bar with a pronated hand grip (palms down) about six inches wider than shoulder width. Unrack the bar and hold it in a locked out position, above the chest but in line with the shoulders. There are only two things to remember when lowering the bar to your chest. First, let the bar descend straight down to the highest point on your chest. Usually that is about a half inch below your nipples. Try to stay as tight as possible during the descent. Be careful not to let the bar “free-fall” from the straight arm position to the chest. Note that it takes more strength to stop the descent of the bar and reverse inertia when you free-fall the weight than it does when you have a smooth controlled descent. Also, when you “free-fall” the weight there is a greater danger for injury. The second point that needs to be made is in reference to the elbows. During the descent, the elbows should be tucked into your sides. Whatever you do, do not let your elbows flare outward during this movement. If
you do, you will decrease your mechanical efficiency for driving the weight off your chest and through your sticking point. Next is the ascent. According to research, lifters should develop a horizontal bar path that's as close to the shoulders as feasible. The displacement of the bar path toward the shoulders reduces the torque, which the lifter is required to generate at the shoulders. The initial movement of the bar from the chest should therefore include a substantial horizontal component toward the head and should gradually continue along this path until completion of the lift. In gym terms, when you push the bar off your chest, gradually drive it back over your eyes until you reach a straight arm or locked out position. As you lower the bar to your chest, inhale and then exhale as you drive the weight back to its starting position. Also, keep your subjects head and derriere on the bench throughout the entire lift. Whatever you do, don't let them arch their back too sharply as to raise their hips off the bench. By arching, the potential for injury to the lower back is significantly increased due to extensive lower back hyperextension. Additionally, any transfer of momentum from the legs to the upper body will result in more lumbar hyperextension. Again, there is a greater potential for injury. Actually, it is a good idea to have your subjects put their feet up on the benchâ€Śby doing this they will position their back so that it is flat on the bench thereby eliminating the arch in their back and also eliminating any drive they would get from their legs. Concerning the latter point, it would make the test a purer assessment of upper body strength. Additional considerations: Once again, it can be seen that biomechanics can significantly affect performance. Consequently, the more standardized you can make the test the greater will be its validity. I know I said that a couple million times.
Deadlift Objective: to measure the strength of the quadriceps, hamstrings, gluteus maximum and minus and rhomboidsâ€Śthe primary muscle being the quadriceps and the lower back. Age level: age 16 through college level. Reliability: Test-retest reliability coefficients of .84 to .96 have been reported. Validity: Face validity is generally accepted for this test. The test correlates .89 with total body strength when it is used to evaluate elite athletes. (Cotton, Biasiotto, and Chissom 1974) Equipment: An Olympic bar, collar and free weights. Directions: Let's discuss grip first. With the conventional deadlift method,(this is the method you want to use for testing) your hands are positioned outside of your legs. Reverse your grip. In other words, one hand should be supinated and the other pronated. This will help cut down on
the torque of the bar. As with the squat, your foot spacing is an individual matter. However, some universal rules persist: point your toes slightly outward, lock your thighs in a just-above parallel position, keep your back tight, straight and in an upright position with your head straight and facing forward. The hardest part of this lift is breaking inertiaâ€Śgetting the weight off the ground. Generally, once you break ground with the weight, the lift is yours, especially if you've kept your hips down. Keeping your hips down is something you'll want to concentrate on. When the weight gets heavy, many lifters have a tendency to raise their hips and drop or dip their back forward. Not only is it nearly impossible to pull the weight from that position, it's extremely dangerous. In fact this may cause some "REAL" trouble when the lift gets beyond the kneesâ€Ślike ripping your freaking lower back in half. When you are in a good position, pull the bar with a smooth, fluid motion. Don't try to jerk the weight from the floor. Remember that the back and thighs work together throughout the entire lift. Consequently, the back and thighs should lock out together at the end of the lift. It's also a good idea to drive your head backward throughout the lift. Everything tends to follow your head. By driving your head back, it will force your shoulders back and your chest up. It will also force you to keep your hips down. One last point: when pulling the weight, keep the bar close to your body. The further the weight is from your body the less leverage you have, and consequently, the harder the lift. In order to lift the weight, inhale slightly and using your thighs and back, stand erect with your arms locked out. Once you're standing erect with arms locked out, lower the weight back to the floor and exhale. Additional considerations: Understand that this lift can be dangerous. So make sure you have picture perfect form before trying them. With that being said here are a few suggestions. At the top of the lift make sure you are standing erect. If you are too far backwards or forwards additional stress will be put on the lower back thereby predisposing you to injury. Although this lift correlates very high with total body strength for elite athletes it is a dangerous lift comparatively speaking.
Military Press Objective: to measure the strength of the anterior deltoids and serratus anterior. Age level: age 16 through college level. Reliability: Test-retest reliability coefficients of .84 to .90 have been reported. Validity: Face validity is generally accepted for this test. Equipment: An Olympic bar, collar and free weights. Directions: Military press is another exercise I am really not to crazy about because of the undue stress they place on the rotator cuffs. The exercise can be performed with the elbows pointed
forward, as in the military press or with the elbows pointed outward, as in the behind-the-neck press. I will start with military presses. Start with your feet shoulder width apart. Grip the bar with a pronated grip with your hands slightly wider than shoulder width. Position the bar across your shoulders and upper chest. Your elbows should be pointed downward and forward so that the bar is in front of the upper chest. Without arching your back, press the weight overhead until your arms are locked out. Pause momentarily at the top of the lift then lower the bar to the starting position. Whatever you do keep tight throughout the entire movement. Donâ€™t arch you back as you press the weight over head if you do you are setting yourself up for a back injury. It should be noted that the reliability coefficients for this test are relatively low ranging from as low as .84 to .90. As you might expect the reliability scores tend to be higher with the more skilled athlete. With unskilled athletes the validity of this test has to be questioned.
Free Weights versus Machines for Testing Over the past several years, much controversy has centered around the question of whether testing using free weights (barbells) or various types of weight machines (Nautilus, Universal, etc.) produces a greater validity for strength and muscular endurance testing. At present, a definitive answer to this question is not available. When comparing strength scores obtained on various types of weight machines, little differences exist between variable resistance machines and constant resistance machines. However, Stone Williams and Cotton (1999) argue that strength testing using free weights is superior to testing with many commercial weight machines (both constant and variable resistance) for the following reasons: ( 1 ) the use of free weights provides movement versatility and allows a greater specificity of testing than weight machines, (2) testing with free weights (unlike many weight machines) involves large muscle groups and multisegment exercise, which forces the subjects to control both balance and stabilizing factors. This type of testing is useful, since most sports require the athlete to maintain balance and body stability during competition. Machines take away the subjects individual lifting groove and force them to follow the track of the machines furrow. Although free weights offer some advantages over commercial weight machines, disadvantages also exist. Possible disadvantages include the potential for injury, extra people required for spotting, and the amount of time required to learn the proper lifting technique. Of course, there are also some major disadvantages and advantages of using machines. The major advantage of using machines is that they are relatively safe. They also require less skill; consequently, the measure is more objective than when using tests that require free weights. Also, machines require less time to change the weights, require fewer individuals to give the test and the movement is the same for each subject being tested. The major disadvantage, especially for a school setting, is the high cost of the equipment.
With the aforementioned in mind, let’s look at some of the test exercises that require machines. Note that I have only presented exercise for muscle groups that were not covered in the free weight section. It should be noted that machines could be used for bench pressing, squats, incline bench presses, military presses etc.
Leg Press Objective: to measure the strength of the quadriceps. Age level: age 16 through college level. Reliability: Test-retest reliability coefficients of .89 to .96 have been reported. Validity: Face validity is generally accepted for this test. The test correlates .87 with squats when it is used to evaluate elite athletes. (Cotton, Biasiotto, and Chissom 1974) Equipment: A leg press machine. Directions: Actually, leg presses are a variation of squats done upside down. In other words, with leg presses you get to sit down while you're doing them. That's one reason why I like them…I am lazy. There are other reasons though too. Leg presses are great for isolating the quadriceps and at the same time maintaining good intensity and they require little skill to perform…a great thing when testing. Since they correlate high (.87) with squats, they could be used as a substitute for the squat test, especially if you are testing elite athletes. Here's how you perform them. Sit in a leg press machine with your feet firmly on the pedals. Your knees should be bent to a right angle and your feet should be pointed slightly outwards. When ready, press the weight upward until your legs are almost straight. Note that your knees should not "lock out" when your legs straighten. This will keep you from hyperextending your knees and will allow you to keep maximum resistance on the quadriceps throughout the exercise. Pause at the top of the lift, and then return the weight under control to the starting position. Don’t use to wide of a foot spacing. The wider you go the less stress you will put on the quadriceps…the muscles you are trying to test here. Your leg spacing should be approximately shoulder width apart. Also, point your toes slightly outwards. This will take stress off your knees.
Lat Pulldowns Objective: to measure the strength of the latissimus dorsi.
Age level: age 16 through college level. Reliability: Test-retest reliability coefficients of .94 to .96 have been reported. Validity: Face validity is generally accepted for this test. Equipment: A lat machine or pulldown machine. Directions: Here's something you may not know. The most effective way to perform pulldowns is to pull to the front of your body…not to the back as most lifters do. The reason is that when you pull to the back the rhomboids and trapezium does the bulk of the work thereby robbing the latissimus dorsi of maximum effort. Also, pulling to the front of the body most closely approximates the insertion angle of the lats. Why do most coaches, teachers, athletes and lifters do pulldowns to the back then? That is easy to answer, because they haven't read my book yet. And don't you dare tell them. Let them buy the book. Thank you! Now I will tell you how to do pulldowns the right way. Sit under the bar of a pulldown lat machine. Grasp the bar with a wide grip so that your arms form a wide V, (Again in testing the lift should be standardized for each subject.) this will minimize the involvement of the biceps. Keep your midsection straight and your arms fully extended. When ready, pull the bar down at a slow to moderate speed…do not jerk the weight. The elbows should be drawn downward toward the sides, keeping the trunk stationary. Arch you back slightly as you pull the weight downward. Note that if you lean backwards too far, you will recruit muscles in the back other than the lats. You just want to lean back slightly and gently. Try to stay fairly upright. Although most lifters pull the weight to their collarbone, the bar needn't be pulled downward beyond the level of the chin. When you reach the bottom of the lift, relax slightly and then return the bar to the starting position. Don’t lean back too far and don’t jerk the weight downward. Pull the weight down in a smooth and controlled manner.
Leg Curls Objective: To measure the strength of the hamstrings. Age level: Age 16 through college level. Reliability: Test-retest reliability coefficients of .90 to .96 have been reported. Validity: Face validity is generally accepted for this test. Equipment: A leg curl machine.
Directions: Lie face down on a leg curl machine. Make sure that your knees are parallel to the axis of the machine's movement arm, and your heels firmly underneath the roller pads. Curl your legs back until your heels touch your buttocks. Pause at this point and then lower the weight back slowly to your starting position. Note that at the point where your heels touch your buttocks, you may get a little attention from members of the opposite sex. That's because at this point in the movement, your derriere is sticking out like a hump on a camel. Don't be self-conscious. Understand that everyone else's derriere does the same thing during this exerciseâ€Śan excellent reason for hanging around the leg curl machine during your workouts.
Leg Extensions Objective: To measure the strength of the hamstrings. Age level: Age 16 through college level. Reliability: Test-retest reliability coefficients of .91 to .96 have been reported. Validity: Face validity is generally accepted for this test. Equipment: A leg extension machine. Directions: Sit on a leg extension machine and hold onto the sides for support. Then slowly straighten out your legs until your knees are completely extended. The entire "rep" should be performed in a slow, deliberate manner, emphasizing the contraction throughout the movement. Keep your back against the back of the bench. Donâ€™t let your hips come off the bench.
Seated Calf Raises Objective: to measure the strength of the gastronomes. Age level: age 16 through college level. Reliability: Reliability: Test-retest reliability coefficients of .91 to .96 have been reported. Validity: Face validity is generally accepted for this test. Equipment: A seated calf machine. Directions: Position yourself in a seated calf machine with the balls of your feet on the platform and the kneepad on the lower part of your front thigh. Slowly lower your heels and let your calf
muscles stretch as far down as possible. Keep your upper body completely still throughout the exercise. Use strictly the calf muscles to do the exercise. Donâ€™t push or lurch up with your thighs. The pads should be placed close to the knees not high on the thighs.