From: TMccull230@aol.com Date: Sat, 3 Feb 1996 Subject: How to Test Leg Strength To test your leg strength you will need to determine your 1RM on a seated leg press. On your first attempt, try to press an amount of weight equal to 2 times your body weight. If that weight is too much or too little, rest 3 minutes and add or remove weight before trying again. Continue to add or remove weight until you locate the amount, to the nearest 10 lbs., that you can press only once. You should be able to press 2.5 times your body weight. If your leg strength is less than 2.5 you need to increase your leg strength. To find the hamstring/quadricep strength ratio you will need to get a 1RM for the leg curl and the leg extension. Once you have determined your best leg curl and best leg extension, divide your leg extension into your leg curl to get the ratio of hamstring to quadricep strength. Example: leg extension is 85 lbs and the leg curl is 50 lbs. 50/85 = 0.59 Your leg curl (ratio) should be at least 75% of your leg extension. If the ratio is <75%, you really need to do some more work on your hamstrings.Ideally, the scores between the two should be about the same, but usually the hamstrings are the weak link. Tom McCullough MS RD CSCS ------------------------------ Response from Michael Carr: Tom, I was amazed to see the signature on this post. Up until now, I've seen nothing but good advice from TMccull230@aol.com, but when I saw this, I couldn't hold back. You know better than most that no two machines are alike, and that only free weight movements can be used for global comparison. For example, at my old gym (was Universe Gym, in Tewksbury MA, now called East Coast Fitness), there were two leg press machines back-to-back. If I tried to press 2.5xBW on the first, I'd get crushed, and yet, I was moving 500 lbs (> 3xBW) on the other for reps. (Back me up on this Motz, if you remember the machines). A slight difference in seat angle, track elevation, and sled weight make a BIG difference. I'd hate to see some pencil-neck throw a few hundred lbs on the former, unlock the stops, and find his knees in his chest half a second later. > To find the hamstring/quadricep strength ratio you will need to get a 1RM for > the leg curl and the leg extension. Once you have determined your best leg > curl and best leg extension, divide your leg extension into your leg curl to > get the ratio of hamstring to quadricep strength. First, I think the leg extension, being an open kinetic joint exercise, is a dangerous exercise go for a 1RM in. Second, the same argument above goes doubly for leg extension/flexion machines. My old gym had a Universal curl on which I was doing about 120-130 with good form (don't get me started on form with these -- tied with side lateral raises as the most ill-performed movement). At the time I was doing the stack (250 lbs) for 6-8 reps on the Nautilus extension. Thus, my ratio would be around 50%. My new gym has the same extension machine, and a Nautilus curl machine, on which I have trouble maintaining proper form with 70 lbs. So now my ratio is only 28%. Which number should I use when comparing myself to your metric? Does it matter that I can stiff-legged deadlift (focusing on the hamstrings) 185 lbs for 10 reps, and conventionally deadlift (focusing on the glutes and quads) about 255 for 10? Now that ratio (73%) is more in line with your numbers: > Example: leg extension is 85 lbs and the leg curl is 50 lbs. 50/85 = 0.59 > > Your leg curl (ratio) should be at least 75% of your leg extension. If the > ratio is > < 75%, you really need to do some more work on your hamstrings. Ideally, the > scores between the two should be about the same, but usually the hamstrings > are the wink link. > Besides all of this, I also think it's wrong to globally characterize strength without respect to one's frame, biomechanical disposition, and injury history. I'd get off my soap-box now, but I'm afraid my weak hamstrings would fail in there role as antagonist to support my step down..... --Michael Carr ------------------------------------------ Tom McCollough responds: Michael Carr : I don't know how much experience you have in performing strength testing (obviously none), but these are some of the most common methods used by exercise physiologists in testing for leg strength and hamstring to quadricep strength ratios. True, free weights are accurate for leg strength, but I would really hate to try to get an inexperienced lifter to utilize the squat as a method to access leg strength. That would be dangerous. Squats involve much more technique and balance than a leg press, thus it is much simpler to teach someone to use. If I am taking on a new client, I want to immediately assess upper body and lower body strength levels. YOU might put them on the squat rack, but that is probably why I have not lost any clients. Again, let me reiterate, if I have a client that can not leg press 2.5 times their body weight, I know to work more on the legs. Then I determine where the weak link is. The hamstrings, the quads, or both. Then I can accurately write an exercise prescription that will build the body properly. These are very simple methods for assessing strength. >Does it matter that I can stiff-legged deadlift (focusing on hamstrings)185 lb >for 10 reps, and conventionally deadlift (focusing on the glutes and >quads) about 255 for 10? NO, it does not. Every biomechanical analysis I have seen of the deadlift showed utilization of the hip flexors, hamstrings, quadriceps, glutes, and erectors. While the quads are actively extending the knee, the hamstrings are extending the hip. Now deadlifts would hardly be a valid assessment of quadracep strength since it is movement that involves more than one joint as well as more than one muscle group. Furthermore, I don't know what you call a stiff-legged deadlift, but as far as I know, this is an exercise that is designed to isolate the erectors (.ie., pulling the weight from the floor with the knee in a slightly flexed position). Even at that, more than one muscle group must work to pull the weight from the floor forming another kinetic chain movement. This is definitely not a valid assessment of the muscles of the hamstring any way you perform it. As far as I am aware there is only one exercise that causes the muscles of the quadriceps to be isolated while performing concentric extension--the leg extension. There is only one exercise that will isolate the hamstring while it is performing concentric flexion--the leg curl. >> On your first attempt, try to press an amount of weight equal to 2 >> times your body weight. > If I tried to press 2.5xBW on the first, I'd get crushed, Michael, use your head, did I say to do 2.5xBW on your first attempt? Next what does the term FIRST ATTEMPT refer to? Again use your head, you are an experienced lifter aren't you? Before one attempts a 1RM should they not first warm up? If you can't do 1/2 your body weight in a warm up what kind of sense would it make to go heavier. I really don't think the readers of this list are as ignorant as you seem to think. >only free weight movements can be used for global comparison. Again you have shown what little you know about strength testing methods, Cybex equipment is used frequently. >First, I think the leg extension, being an open kinetic joint exercise, is a >dangerous exercise go for a 1RM in. Again you are showing your lack of knowledge. It is very common to isolate muscles and assess 1RM strength. Have you not ever taken a physiology of exercise course? These kind of assessment are done frequently in labs even on the undergraduate level. >. I'd hate to see some pencil-neck throw a few hundred lbs on the former, The reason many of us spend hours contributing to this list is to help new weight lifters (we certainly don't get paid). Weight lifting has been my life for about 25 years. I really hate to see this kind of attitude. I really think all of us were beginners at one time or another. Tom McCullough MS RD CSCS ------------------------------