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Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=ipsm20 Download by: [FU Berlin] Date: 03 May 2017, At: 02:18 The Physician and Sportsmedicine ISSN: 0091-3847 (Print) 2326-3660 (Online) Journal homepage: http://www.tandfonline.com/loi/ipsm20 Hamstring/Quadriceps Strength Ratios in Collegiate Middle-Distance and Distance Runners Alfred Morris PhD, Louis Lussier MD, PhD, Gerald Bell EdD, PT, ATC & Jeffrey Dooley MS, ATC To cite this article: Alfred Morris PhD, Louis Lussier MD, PhD, Gerald Bell EdD, PT, ATC & Jeffrey Dooley MS, ATC (1983) Hamstring/Quadriceps Strength Ratios in Collegiate Middle- Distance and Distance Runners, The Physician and Sportsmedicine, 11:10, 71-77, DOI: 10.1080/00913847.1983.11708658 To link to this article: http://dx.doi.org/10.1080/00913847.1983.11708658 Published online: 11 Jul 2016. Submit your article to this journal View related articles Citing articles: 2 View citing articles http://www.tandfonline.com/action/journalInformation?journalCode=ipsm20 http://www.tandfonline.com/loi/ipsm20 http://www.tandfonline.com/action/showCitFormats?doi=10.1080/00913847.1983.11708658 http://dx.doi.org/10.1080/00913847.1983.11708658 http://www.tandfonline.com/action/authorSubmission?journalCode=ipsm20&show=instructions http://www.tandfonline.com/action/authorSubmission?journalCode=ipsm20&show=instructions http://www.tandfonline.com/doi/mlt/10.1080/00913847.1983.11708658 http://www.tandfonline.com/doi/mlt/10.1080/00913847.1983.11708658 http://www.tandfonline.com/doi/citedby/10.1080/00913847.1983.11708658#tabModule http://www.tandfonline.com/doi/citedby/10.1080/00913847.1983.11708658#tabModule Hamstring/ Quadriceps Strength Ratios in Collegiate Middle-Distance and Distance Runners Alfred Morris, PhO Louis Lussier, MD, PhD Gerald Bell, EdO, PT, ATC Jeffrey Dooley, MS, ATC ln brief: lt has been noted that the hamstring 1 quadriceps isometric strength ratio in men should be approximately 50% to 60%. We studied hamstring/ quadriceps strength ratios in collegiate varsity middle-distance runners and found that they varied between .62 at slow speeds of muscle contraction and .87 at faster speeds. These results confirm previous reports that knee flexor 1 extensor ratios (peak torques) vary with angular joint velocity. Physicians, trainers, and therapists should consider velocities of muscle contraction when determining hamstring/quadriceps strength ratios. S keletal muscle strength, power, and endurance are important in most sports. Muscle asymmetry in right and left limbs has been suggested as a predisposing factor in muscle strains. Sev- era! a ut hors have discussed preseason evalua- tion of the athlete and have incorporated strength testing with this in mind.' ... Strength evaluation is now considered to be an impor- tant part of profiling athletes in various sports. '- 7 Burkett' studied muscle imbalance in foot- Dr. Morris is assistant director for research and educa- tion and associate professer in the division of rehabilita- tion education at the University of Illinois in Champaign. Dr. Lussier, Dr. Bell, and Mr. Dooley are in the department of physical education at the University of Illinois in Urbana. Dr. Morris is a fellow and Dr. Lussier, Dr. Bell, and Mr. Dooley are members of the American Collage of Sports Medicine. Titi PltYSICIAN AND SPORTSMEDICINE e Vol 11 • No. 10 • Oc lober 83 Photo: Curt Beamer © 1983 The hamstringlquadriceps ratio is not a fixed value and should be evaluated at speeds close to the speed of contraction in the athlete's event. bali players and sprinters and concluded that it was a predisposing factor in hamstring strains. He a iso reported isometric hamstring/ quadriceps ratios in these two populations. Klein and Allman' suggested that distance runners who have muscle imbalances are more prone to lower limb injuries. No one has reported strength ratios in middle-distance runners. Klein and Altman' suggested that the hamstring/ quadriceps ratio is important in preventing injuries. Although its clinical significance has not been weil established, a balance between agonist and antagonist mus- co/li imted 71 strength ratios continued Table 1. Descriptive Data of Male Runners Age Helght Welght Subject (yr) (ln.) (lb) 1 18 71 140 2 19 70 125 3 22 71 . 155 4 20 70 134 5 20 691/2 132 6 22 72 145 7 20 71 140 8 21 69 148 9 18 73 165 10 18 66 1/2 133 11 22 72 155 12 21 72 138 Mean±SD 20.1 ± 1.18 70.6±0.62 142.5±9.04 cles as well as balance in right and left limbs are important in sports that involve running. Thistle et al9 evaluated athletes for strength and power with isokinetic testing using var- ious protocols. lsokinetic evaluations provide the researcher with a quantitative written record of the torques developed about a joint throughout the whole range of motion. Such values have been used to describe healthy ·populations as weil as people with joint dis- abilities/·'"11 and such testing has become a standard method of testing various athletic populations for muscular strength, power. and endurance in sports medicine clinics throughout the country. Middle-distance runners tend to exhibit less lower limb strength than sprinters, but they are susceptible to muscle strains just as any other runner. 12'14 The purpose of this study was to measure the strength of knee flexors and extensors in a collegiale tçam of cross-country and middle-distance runners. ln addition, we compared strength between 72 Prlor Best lnjury Event Performance Hlstory 1/2 mile 1:55.2 No major injury 2 miles 9:17 None 3,000 meters 9:06 Left foot tendinitis (metatarsals) 1 mile 4:05 None 10km 29:41 None 10km 29:47 Strained Achilles tendon 5miles 25:32 Righi knee tendinitis 1 mile 4:20 Sprained ankles (bilateral) 1 mile 4:16 Righi sartorius strain/left quadriceps strain 2 miles 8:55 None 5 miles 24:15 Stress fracture of tibia, age 4 yr 1,500 meters 3:43.9 Right hamstring, slight strain right and left sides and between agonists and antagonists. Subjects Twelve members of a varsity track and cross-country team in the Big Ten conference were recruited for this study. AH were healthy men with no acute or chronic injuries. The participants. who are described in table 1. ali signed standard university-approved in- formed consent forms. Ail runners were shown to be right-leg dominant.'j Methods Subjects were tested for knee extension and knee flexion on a Cybex Il isokinetic dyna- mometer (Cybex Division, Lumex lnc. Bay- shore. New York 11706). The subjects were positioned on the dynamometer by the same experimenter throughout the study. The dy- namometer was calibrated daily throughout the study according to the procedures sug- gested by the Cybex manufacturer. continued Vol11 • No. 10 • Oc lober 83 e THE PHYSICIAN AND SPORTSMEDICINt: strength ratios continued Subjects were tested bath isokinetically and isometrically. The angle for isometric knee extension and knee flexion was 50° (full extension= 0°). Morris'~ has shawn that this angle gives reliable measures and also is one of the strongest points in the range of motion at the knee. A goniometer was used to ascer- tain the proper knee angles with reference to the lateral malleolus, lateral femoral condyle, and greater trochanter. Isokinetic testing was do ne at 30°1 sec, 60° 1 sec. 180° 1 sec, 240° 1 sec, and 300° 1 sec. The reason for these different speeds of mus- cle contraction was to examine hamstring/ quadriceps ratios at fast (240° 1 sec and 300°1 sec), medium (180° 1 sec), and slow (30° 1 sec) speeds. The arder of tes ting was balanced for ali subjects. 1" Counterbalancing the arder of testing for each subject reduces the chance of fatigue or the learning effect influencing the data collection. Ali measures were collected on bath limbs, bccausewc compared and contrasted strength ratios within each limb and betwecn right and !cft limbs. Testing for each athlete was completcd in a single session. Johnson and Siegel'' have reported rcliability coefficients of .93 and .94 for such isokinetic tes ting of knee flexion and extension. Upon reporting to the laboratory subjects were briefcd as to the nature of the test and allowed severa! warm-up trials after they were positioned on the apparatus. The experimenter carcfully positioncd each sub- ject on the testing table and stabilized ali body parts. The subject grasped the sides of the testing table for support. and straps were secured around the chest and pelvis ta stabi- lize the upper body.'~'" For isokinetic testing ali subjects were told ta move through the entire range of motion of knee flexion and extension as hard and as fast as possible. Peak torques were recorded using the average of three contractions at each speed. A rest interval of 60 ta 90 seconds was allowed between each set of contractions. For isometric contractions the subject was posi- tioned and instructed to build a maximal voluntary contraction as rapidly as possible, without any jerking. and hold it until told to stop. The experimenter had the subject reach his maximal voluntary contraction and hold it Titi PltYSICIAN AND SPORTSMEDICINE e Vol 11 • No. 10 • Oc lober 83 for 1 to 3 seconds. The average of three con- sistent plateaued trials was used as the recorded value. After testing one extremity, the subject was allowed ta move about the la bora tory for a few minutes and then reposi- tioned for testing the opposite extremity in the same manner. Results The greatest torque was recorded at an isokinetic speed of 30°1 sec for bath knee extension and flexion. The runners developed a mean of 139.2 ft-lb of torque in extension and 87.0 ft-lb of torque in flexion. Table 2 shows ali strength values under ali testing conditions. At an isokinetic speed of 60°1 sec the torques were comparable ta those of 30°1 sec. Isometric values were 95% of the isokinetic torques at 30° jsec and 60° /sec for knee flexion and only 81% of the torque devel- oped at 30° /sec in knee extension. At speeds beyond 60°1 sec the torques dropped progressively as speed increased to 180° 1 sec, 240° 1 sec, and 300° 1 sec. Torque values of 88.2, 70.6, and 59.3 ft-lb were recorded in knee extension and 66.1. 57.9, and 51.4 ft-lb in knee flexion, respectively, at the speeds stated above. The hamstring/ quadriceps ratio was at its lowest at the speeds that produced the highest torques, corresponding ta .63 and .65 at 30°1 sec and 60°1 sec. The ratios then in- creased to .76 .. 83. and .87 as the angular speed was increased ta 180°1 sec, 240°1 sec, and 300°1 sec. The ratio of torques developed isometrically is comparable ta that recorded at 180° /sec (.74). When ratios of torque per pound of body weight were calculated. these ratios ap- proached 1 (.98and .93)atspeedsof30°/sec and 60°1 sec for knee extension. The isometric torque was ont y . 79 body weight. The ratios at the higher speeds were .62, .49, and .41 for 180°1 sec, 240°1 sec, and 300°1 sec. The ratio ofhamstring torques to body weight hadhigh values of .62 and .61 at 30° /sec and 60° /sec, and .58 at the isometric setting. The decrease at the highcr speeds was not as great. with values of .46. .40, and .36 at 180°1 sec, 240° 1 sec, and 300°1 sec. Differences from one Iimb ta the other continued 75 The hamstring/ quadriceps ratio was lowest at speeds producing the highest torques. strength ratios continued Table 2. Hamstring/Ouadriceps Torque in 12 Runners (Mean ±SD) in Ft-lb* Hamstring torque (flexion) lsomelric lsokinetlc 30° /sec 60° /sec 180° /sec 240° /sec 300° /sec fl-lb 82.7±14.63 87.0±1004 86.7±12.91 66.1±1083 57.9±10.96 514±1049 Newton- rn et ers 112.1±19.84 118.0±1361 1176±1751 896±1469 785±14.68 697±14.22 Quadriceps torque (extension) .Ft-lb Newton-meters 113.2±18.75 139.2±17.32 132.6±16.59 882±1494 70.6±13.55 593±1241 153.5 ± 28.42 188.7 ± 2349 179.8 ± 22 50 119.6 ± 20.26 95.7 ± 18.69 804 ± 16.83 "1 ft-lb= 1 356 Newton-meters varied between 6% and 12% for the quadri- ceps. with the highest mean difference recorded at the isometric sctting. At the isoki- netic speeds the largest mean difference was 9%. recorded at 300° j sec. Hamstring torque differences varied betwecn Il% and 7% with the highest values recorded between 180° j sec and 300° 1 sec. lsometric strength values are known to vary at different angles of contraction for the knee joint.'\ Discussion Thesc runners were tested at the end of a cross-country (tate fall) season. They were weil trained and in excellent physical condi- tion, and none of them reported any knee condition or thigh muscle strain that would affect the results. The forcc-velocity curves obtained are similar to those reported by Wyatt and Edwards 111 and by Thorstensson et al.'" except for the isometric values. Thor- stensson et al" recorded significantly higher values at the isometric setting with maximal torques recordcd at 75° of flexion. We recorded grea ter torques at the isokinetic set- ting of 30° j sec and 60° j sec than in the iso- metric mode. The isometric torques were recorded with a knee angle of 50° of flexion. Wc observed decreasing torques with in- creasing angular velocities. The rate of decrease was different between the quadri- ceps and the hamstring. There was a 41% drop in torque values for the hamst~ing. and the drop in torque for the quadriceps was 57%. Thorstensson et al'" reported that a 76 higher percentage of fast-twitch fibers in the quadriceps tended to be related to higher torques at higher speeds. ln this study these middle- and long-distance runners might be expected to have mixed fiber types in their quadriceps. because they exhibitcd decreased torque at higher spceds. CampbelL'" in his study of distance runncrs. reported similar findings. If the hamstrings could be consid- ered power muscles. then they may present a grea ter proportion of fast-twitch fi bers. (Un- fortunatcly. such data arc not available for human hamstrings.) This might explain the relatively higher torques of the hamstrings at the higher speeds. The torques developed by the quadriceps approach the athlete's body weight at a set- ting of 30°1 sec. which wc typically cons id er an acceptable leve! of power for an athlete after a rehabilitation program.i" Since these runners were typically lightweight athletes. the torques recorded did not exceed 150ft-lb. 1t has been our experience that sprinters and hurdlers typically excced their body weight in the maximal torques recorded.~' The hamstring/ quadriceps ratio varied with the angular velocity setting. At the slow speeds we obtained values of about .65. which compare to Burkett.' who reportcd .65 in sprinters. However. our ratios are lower than those reported by Wyatt and Edwards'" at the slower speeds. They observed .72 in their hamstring/ quadriceps ratio in men at 60° j sec. A value calculated from Campbell'" yielded a ratio of .55. At the fastest speed of 300° j sec the hamstringj quadriceps ratio ex- Vol11 • No. 10 • October 83 e THE PHYSICIAN AND SPORTSMEDICINt: ceeded .85 in our study. This is slightly higher than that reported by Wyatt and Edwards. 1" Howevei-. they did not use athletes for their subjects. It should also be noted that the body weight ratios (torque/ body weight) are lower for the subjects of Wyatt and Edwards 1" than for our subjects. Differences from side to side were between 6% to 9% for the quadriceps and 8% to Il% for the hamstrings for ali movement condi- tions. The greatest discrepancy was noted in the isometric condition for knee extension. Differences were below the value of 10%. which has been proposed as an acceptable norm by sorne authors.' 11 Sorne sports medi- cine professionalsnow suggest 5% as a limit for side-to-side differences when using total lower limb strength. 11 Conclusions In this study varsity track and cross- country male athletes were not able to devel- References 1. Hurkett LN: Ülltsative fac~ors in hamstring stmins. Med Sei Sports 2(Spring):39-42. 1970 2. Nicholas JA. Stritak AM. Vcras G: A study of thigh muscle weakness in different pathological states of the lower extremity. Am .1 Sports Med 4(November-December):241-248. 1976 l Nicholas JA: Risk factors. sports medicine and the orthopedie system: an ovcrvicw . .1 Sports Med 3(Scptember-Ociober):243-259. 1975 4. Sapega AA. Nicholas JA: The clinical use of mus- culoskclctal protïling in orthopedie sportsmcdi- cinc. Ph ys Sportsmcd 9( Apri1):80-88, 1981 5. Smith DJ. Quinncy HA. Wenger HA. ct al: lsoki- nctic tor4ue outputs of profcssional and elite ama- teur icc hockey plll'ycrs. Journal nf Orthopacdic and Sports Physical Thcmpy 3(Fall):42-47. 1981 6. Parr RH. Hoover R. Wilmorc .IH. ct al: Profes- sionul baskctball pluyers: uthlctic profiles. Phys Sportsmed 6(April):77-84. 1978 7. Pyke FS. Minikin HR. Wood man LR. et al: lsoki- nctic strcngth and maximal oxygcn uptakc of traincd oarsmcn. Can J Appl Sport Sei 4(Dc- cember):277-279. 1979 8. Klein KK. Allman FL: The Knee in Sports. Aus- tin. TX. Jcnkins Publishing Co. 1969 9. This tic HG. Hislop .1 H. Moffroid M. et al: lsoki- netic contraction: a new concept of rcsistive cxer- cise. Arch Phys Med 48(.1une):279-282. 1967 10. Wyatt M P. Edwards AM: Comparison of 4uad- riceps and hamstring tor4ue values during isnki- netic exercise. Journal of Orthopaedic and Sports Physical Therapy 3( Fall):48-56. 1981 Titi PltYSICIAN AND SPORTSMEDICINE e Vol 11 • No. 10 • Oc lober 83 op isometric torques grea ter than th ose devel- oped at 30°1 sec at a knee flexion angle of 50°. As the velocity of contraction increased, torques decreased at a greater rate in the quadriceps than in the hamstrings, and the hamstring/ quadriceps ratio increased. The hamstring/ quadriceps ratios varied between .62 at the slow isokinetic speeds (30° 1 sec) an.d .87 at fast speed (300° 1 sec). The hamstring/ quadriceps ratio does not appear to be a fixed value, and it would probably be best evaluated in conditions where the veloc- ity of contraction approximates the speeds of contraction used in the athlete's specifie event. Hamstring/ quadriceps ratios may be specifie to the demands put on the athletes by the sports in which they compete. Addrcss corrcspondcncc to Alfred F. Morris. l'hi>. University of Illinois. Rchahilitation Education Center. 1207 S Oak St. Rm 102. Ch:tmpaign 61820. Il. Gleim GW. Nicholas .lA. Webb .IN: lsokinetic evaluation following leg injuries. Phys Sportsmed 6(August):74-82. 1978 12. Krissoff WB. Fcrris WD: Runncrs' injuries. Phys Sportsmed 7( December):53-70. 1979 Il Mann RA. Hagy .1: Binmcchanics of walking. running and sprinting. Am .1 Sports Med 8 (Scptcmbcr-Octobcr):J45-350. 1980 14. Clement DB. Taunton JE. Smart GW. ct al: A survcy of overusc running injuries. Phys Sports- mcd 9(May):47-5S. 19SI 15. Morris AF: Myot;~tic rctlcx effccts of bilateral reciproc;~l leg strength. Am Correct Thcr J 28 (January-Febru;~ry):24-29. 1974 16. Morris AF: Effccts of f;~tiguing isometric and iso- tonie exercise on resisted and unresistcd reaction time components. Eur .1 Appt Physiol 37(Jun 15):1-11. 1977 17. Johnson .1. Siegel D: Reliability of an isokinctic movcmcnt of the knee extcnsors. Res Q 49 (March):88-90. 1978 18. Thorstensson A. Grimby G. Karlsson .1: Force- vclocity relation and lïber composition in human knee extensor muscles. J Appt Physiol 40(Janu- ary):l2-16.1976 19. Campbell DE: Generation of horscpower at low and high vclocity by sprinters and distance run- ncrs. Res Q 50(March):l-8. 1979 20. Lussier L Bell G: (Unpublishcd data. 1981) 21. Lussier L. Bell G. Dooley J. et al: (Unpublished data. 1981) · 77
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