Why would a bodybuilder show well-developed quads, but weak hamstrings? A lot has to do with the disproportionate level of strength between the front and rear thigh muscles. The frontal portion of the legs are far stronger, and are therefore capable of hoisting much heavier weight compared to the relatively weaker hamstrings. In addition, many bodybuilders pay far more attention to training their quads in comparison to their "hams," which often just get some cursory treatment following an intense quad workout. Such a scenario not only sets you up for a lack of overall thigh symmetry, but also sets the stage for a likely future hamstring injury. These injuries usually occur because of a lack of strength balance between the quads and the hams. Another frequent cause of injury, which is common in runners, is a hamstring tear or strain. This is caused by sudden stress imposed on tight hamstring muscles. In years past, athletes were often advised to warm-up their hamstrings with a stretching session. The object was to remove some of the "coldness" and muscle tightness in the hams so as to help prevent injury. A better way to warm-up the muscle is to do light activity first that involves the muscle, such as an easy jog or walk, followed by a brief stretching session.
When it comes to training the hams, bodybuilders and others engaged in weight-training have a number of exercises to choose from. The most common exercises for this purpose include the following: leg curls, either standing or lying on a machine; stiff-legged deadlifts; good morning exercise, which involves placing a barbell across the shoulders, then bending forward; and more specialized exercises, such as the glute-ham raise, which was popularized by the Russians years ago, and involves use of a special type of bench. Since the hamstring muscles attach at both the hips and behind the knees, bodybuilders are often advised to do exercises that involve both these muscle attachments to achieve complete development. In practical terms, this usually means doing a leg curl exercise and a standing stiff-legged deadlift, with the latter exercise working the hip attachment of the hamstrings. A variation of the stiff-legged deadlift is the Romanian deadlift, which is a more partial movement than the stiff-leg version.
When bodybuilders train their hamstrings they are often targeting what they call "the leg biceps." Ostensibly, this refers to the biceps femoris. But, as noted above, the biceps femoris is only one of three hamstring muscles, and to get that massive, full appearance requires training all three muscles of the hamstrings. The salient question is: what are the best exercises for this purpose?
A new study featured 12 trained men who did four of the most common hamstring exercises: leg curl, good morning, glute-ham, and Romanian deadlift. The muscle activity of the men was monitored while they did these exercises through the use of an electromyograph machine, which involves placing electrodes over the active muscles, which then transmit electrical activity elicited in the muscles by exercise to a computer. The primary finding of the study was that the semitendinosus muscle was the portion of the hamstrings most activated in the usual hamstring exercises. The maximum muscle stimulation of the hams was induced by the glute-ham and Romanian deadlift exercises. These were the only two exercises that significantly also trained the biceps femoris.
If there is a practical implication from this study, it's that the old technique of combining a flexion exercise such as leg curls with a stretching movement, such as stiff-legged or Romanian dealifts, still makes sense. In fact, not doing both types of exercise means that you will never fully train the hamstrings, nor will you acheive the level of muscle density and strength possible in the hamstrings. As for the glute-ham exercise, that isn't available in many gyms, and is awkward to do until you get used to it. But if it's available, it could make a big difference in your hamstring development, especially if you follow it with stiff-legged or Romanian deadlifts.
McAllister, MJ, et al. Muscle Activation during various hamstring exercises.J Str Cond Res 2013: in press.
©,2013 Jerry Brainum. Any reprinting in any type of media, including electronic and foreign is expressly prohibited.
Have you been ripped off by supplement makers whose products don’t work as advertised? Want to know the truth about them? Check out Jerry Brainum's book Natural Anabolics, available at JerryBrainum.com.
Want more evidence-based information on exercise science, nutrition and food supplements, ergogenic aids, and anti-aging research? Check out Applied Metabolics Newsletter at www.appliedmetabolics.com.
The Applied Ergogenics blog is a collection of articles written and published by Jerry Brainum over the past 20 years. These articles have appeared in Muscle and Fitness, Ironman, and other magazines. Many of the posts on the blog are original articles, having appeared here for the first time. For Jerry’s most recent articles, which are far more in depth than anything that appears on this blog site, please subscribe to his Applied Metabolics Newsletter, at www.appliedmetabolics.com. This newsletter, which is more correctly referred to as a monthly e-book, since its average length is 35 to 40 pages, contains the latest findings about nutrition, exercise science, fat-loss, anti-aging, ergogenic aids, food supplements, and other topics. For 33 cents a day you get the benefit of Jerry’s 53 years of writing and intense study of all matters pertaining to fitness,health, bodybuilding, and disease prevention.
See Jerry's book at http://www.jerrybrainum.com
The Glute-Ham bench