Exercise athletes JERRY R.
performance of collegiate
rodeo
MICHAEL C. MEYERS,*† PhD, JOHN G. WILKINSON,‡ PhD, ELLEDGE,§ PhD, HOMER TOLSON,§ PhD, JAMES C. STERLING,* MD, AND J. RICHARD COAST,§ PhD
From *The Texas
Sports Science Institute, Sugar Land, Texas, the ‡School of Physical & Health Education, University of Wyoming, Laramie, Wyoming, and the §Department of Health & Physical Education, Texas A&M University, College Station, Texas
ABSTRACT
subjective analyses derived from limited measurements strength and speed. Subsequent conditioning or training programs were also modified from this original general concept. Within the last decade, a better understanding of the physiologic responses to exercise and concomitant advances in technology have generated sport-specific training and on
of
In this study we examined the physical, hematologic, and exercise response of 20 male and 10 female athletes of the National Intercollegiate Rodeo Association, Central Rocky Mountain Region. Male subjects were grouped by roughstock, steer wrestling, and roping events. Female athletes were grouped separately. Maximal aerobic capacity, pulmonary ventilation, respiratory exchange ratio, energy expenditure, maximal heart rate, blood pressure, treadmill time, pre- and postexercise lactate, percent body fat, lean body mass, blood chemistry, serum lipids, and reaction/movement time were analyzed by event. No significant differences (P > 0.05) were found in any of these categories between male events. Mean resting blood chemistry parameters of rodeo athletes were within normal ranges. Steer wrestling athletes possessed greater body size and lean body mass than other groups. When analyzing body composition, blood pressure, and total cholesterol:high-density lipoprotein (HDL) cholesterol ratios, results indicate average to low risk for coronary heart disease. When compared to other intermittent-activity sport athletes, college rodeo athletes appear to have similar aerobic capacities, but possess lower lean body mass and greater percent body fat.
rehabilitation programs for traditional athletes based on a wide array of quantitative measurements. Research on the sport of rodeo is limited. The majority of studies have primarily focused on injuries and psychologic aspects of these nontraditional competitors. 15, 16, 28,30-32 The of physiologic fitness status, the
testing, however, may identify present potential for athletic performance, the predisposition to injury, and possible coronary risk concerns and have substantial application to the understanding of this unique sport and the development of sport-specific training programs. At this time, no published studies exist that examine the exercise performance of collegiate rodeo athletes. Rodeo competition is an activity that is basically intermittent in nature, with short periods of highly intense activity. However, as in any sport, the rodeo competitor still requires an aerobic conditioning protocol. Studies have indicated that, by the end of a game, cardiovascular fitness significantly influences the onset of fatigue and the performance potential of athletes subjected to repetitive, high-intensity activity. 14 Physiologic testing of athletes has demonstrated that those athletes who exhibit low aerobic capacity and high percent body fat have a higher incidence of fatigue and show decreases in performance levels.2’ This may ultimately be viewed as a predisposition to injury,’ since injury potential is inversely associated with state of training. Although not conclusive, additional studies have indicated the potential for significant reduction in musculoskeletal injuries resulting from the identification and subsequent enhancement of use
Sports medicine specialists and coaches have continually searched for ways to identify and enhance athletic performance and minimize the risk of injury. Early characterization of athletes was not sport specific and was primarily based t Address correspondence and reprnt requests to. Michael C Meyers, PhD, The Texas Sports Science Institute, 1250 Shorelne Drme, Suite 295, Sugar Land, TX 77478 410
411
muscular strength,
flexibility, and endurance in various ath-
letes.5,21,54 While event-specific strength and conditioning protocols for rodeo have been subjectively prescribed,52 a generalized exercise prescription for the rodeo athlete would be limited without adequate physiologic data. Traditional sport studies have also indicated that physiologic characteristics of athletes varied between sports and between player position.29,44,53,55 Therefore, the purpose of this study was to describe the physical, hematologic, and exercise response of collegiate rodeo athletes in a given event and compare results to other traditional athletes.
15-second average of the data. Blood pressure was monitored at prescribed intervals from rest through the exercise bout and recovery. Venous blood samples for the determination of lactate accumulation were taken via finger sticks from each subject immediately before and after the maximal exercise tests. Blood lactate concentrations were measured in duplicate using a YSI model L23 auto analyzer (YSI Inc, Yellow Springs, OH). Height and weight were determined by calibrated scales, and body composition was determined by hydrostatic weighing techniques. Residual volume was estimated in accordance with standard procedures.&dquo; Lean body mass (LBM) and percent body fat were calculated from body density
manually
MATERIALS AND METHODS
values.’
Subjects
using a Lafayette reaction/movement timer (model 63016, Lafayette Instruments, Lafayette, IN) equipped with visual
During the 1988 and 1989 collegiate rodeo season, physiologic assessments were performed on 20 male and 10 female athletes of the National Intercollegiate Rodeo Association (NIRA), Central Rocky Mountain Region. The majority of athletes were presently or formerly high school or college champions in their respective events. These athletes initially reported to the Human Energy Research Laboratory (2200 meters above sea level) at the University of Wyoming in the morning after a 12- to 14-hour fast. Data were collected on all athletes to obtain the following information: anthropometric status and body composition, cardiovascular endurance, resting blood chemistry, postexercise blood lactate, coronary risk, and visual reaction/movement time. Each individual test battery was completed within the same day and all testing was completed within a 2-week period.
stimulus and 2 response keys.lO,46 There is substantial variation in protocols found among studies using response key testing; we chose a distance of 17 inches from start to target key to allow optimal arm movement with limited shoulder involvement. Each subject was initially given 5 visual warm1 trial), followed by 10 visual stimuli up trials (1 stimulus randomly given in time increments ranging from 1 to 4 seconds. Life-style and nutrition profiles were determined using a standard self-response, laboratory-developed questionnaire to identify coronary risk factors and dietary history of each subject. Questions pertaining to family history of injury, illness, and life-style were also included.
Data
analysis
Procedures
Data
were
Mean visual reaction and movement times were quantified
After obtaining written informed consent from both subjects and coaches, and clearance from the university human research committee, 2 X 10 ml blood samples were drawn from an antecubital vein by a certified hemotechnician and sent to a certified hospital laboratory (College of American Pathologists) for determination of blood electrolytes, cholesterol, triglyceride, glucose, and complete blood count. Serum high-density lipoprotein cholesterol concentration was analyzed in the human performance laboratory by enzymatic
technique. 41 Cardiovascular endurance was determined by having subjects complete a maximal graded exercise teSt4 on a Quinton 24-72 treadmill (Quinton Instruments, Seattle, WA) with heart rate data continually recorded and calculated using a SensorMedics Horizon electrocardiograph (SensorMedics, Anaheim, CA). Electrode lead placement was performed according to the Mason-Liker modified 12-lead system for treadmill stress testing.22 Ventilatory and metabolic variables, i.e., aerobic capacity (VOZ max), ventilation (VE max), and respiratory exchange ratio, were determined breath by breath on a SensorMedics Horizon 4400tc metabolic cart following autocalibration using gases of known concentrations. Maximal V02 and VE values were calculated from a
=
analyzed by event, with male athletes grouped by roughstock (bull riding, bareback riding, saddle bronc riding), steer wrestling, and roping events (including either calf or team roping). Female athletes participating in barrel racing, goat-tying, and break-away roping were grouped separately. Final analysis comprised four categories consisting of nine collegiate events. Test-retest reliability procedures were performed to identify possible physiologic response distortion. Pearson product-moment correlation techniques were applied to assess significant association between dependent variables. Factor analysis procedures were then used for data reduction to assess each variable’s strength of association and to obtain factor scores to use as dependent variables. This reduced the number of variables to compare for the differences between events. After the initial factor method of principal component, eigenvalues of the correlation matrix revealed that 100% of the cumulative data were contained in two factors. With additional varimax rotation and subsequent rsquared procedures, the variables of body fat and cholesterol were chosen for further analyses. Analysis of variance (ANOVA) using General Linear Model (SAS Institute Inc, Cary, NC) procedures43 only revealed significant gender differences (P < 0.05) in percent body fat. Considering the difference in physical demands between male and female events,
412
direct comparison between gender was not made. However, for descriptive purposes and comparison with traditional athletes, all data are presented.
The mean anthropometric and body composition values of collegiate rodeo athletes by event are presented in Table 1. Steer wrestlers were heavier and had more lean body mass than males in the roughstock and roping events. Roughstock were
shorter than males in the roping and steer
wrestling events. Mean exercise response of collegiate rodeo athletes by presented in Table 2. No differences in VE max, V02 max, maximal respiratory exchange ratio, energy expenditure, maximal heart rate, blood pressure or maximal time on the treadmill were found between males in the roughstock, roping, and steer wrestling events. Selected mean resting blood chemistry parameters of collegiate rodeo athletes, as shown in Table 3, were within normal ranges across all events. Among the steer wrestling group, however, values were lower across most variables when compared to the roughstock and roping groups. Mean reaction, movement, and total response times of collegiate rodeo athletes by event are shown in Table 4. No differences were found between male events. Visual reaction event is
TABLE 1 Mean
anthropometric and body composition data of collegiate rodeo athletes by event’
a Values
b
and movement
are means
± SEM.
Body composition Past studies have indicated that low percent body fat values are typically observed in athletes involved in extreme anaerobic competition. 12 Whether this is a physical requirement for success in various sports or simply because of stereotypic selection by coaches is not conclusive. The low percent fat values found among roughstock riders in this study, however, support this theory, reflecting a somatotype typically seen in this physically intensive, 8-second event. A mean body fat of 12.0% among the male subjects was lower than that reported in professional football55 and ice hockey players,42 but higher than reported percentages in professional baseball,6,19 basketball, 17 soccer,&dquo; and rugby players.&dquo; Since performance is inversely related to excess body fat,2’ the high percent body fat values observed among steer wrestlers and the female rodeo athletes, in relation to established athletic norms, pose some concern for improvements in the physical conditioning of athletes in this sport. This higher body fat among the steer wrestlers might be useful, however, when noting the nature of the event, in which a large body size and higher percent body fat may be advantageous when wrestling an animal of this size. This could be considered a similar argument to that for a higher body fat percentage in football linemen and linebackers. Steer wrestlers possessed greater body size than found among athletes in other male events that, in this study, led to a greater lean body mass. When compared to other intermittent-activity sports (Table 5), lean body mass among college rodeo competitors was lower than lean body mass found in athletes competing in football, basketball, and baseball.6,37,55
TABLE 2 Mean exercise response of collegiate rodeo athletes
° Values
msec
DISCUSSION
RESULTS
athletes
time by event ranged from 253 to 275 time from 123 to 157 msec.
are means
±
by
eventa
SEM.
RER, respiratory exchange ratio; METS,
energy
expenditure; HR,
heart rate; Tmax, treadmill time; BP, blood pressure.
413 TABLE 3 Mean
° Values
are
resting blood chemistry of collegiate rodeo athletes by event’
means ± SEM.
TABLE 4 Mean
reaction, movement, and total response time rodeo athletes by eventa
° Values
are
of collegiate
means ± SEM.
TABLE 5 Mean
physiologic comparison between male collegiate rodeo athletes and athletes in other intermittent-activity sports
° Values obtained from work done
Aerobic
on a
cycle ergometer.
capacity
When comparing maximal aerobic capacity with athletes involved in intermittent-activity sports (Table 5), male rodeo athletes exhibited V02 max values similar to elite Olympic basketball, water polo, and gymnastic athletes, and higher than values reported in weight lifters.51 These values for rodeo athletes were also similar to results reported in professional football,55 basketball,&dquo; and baseball players.6,19 As expected, when compared to high-aerobic events, both male and female rodeo subjects possessed lower V02 max and VE max than observed in middle and long-distance
runners,11 cyclists, swimmers,9~51 soccer players,41 triathletes,44 and speedskaters.39 However, because the stress tests administered to subjects in this study at 2200 meters above sea level, B702 max could be underestimated by approximately 8% as compared to sea level values.34 In addition, when resulting V02 max and energy expenditure data in this study were compared to established norms,40,48 male rodeo subjects were considered to possess above average aerobic capacity while female subjects possessed below average to average aerobic capacity. This suggests that training and competing in the male rodeo events (i.e., roughstock, roping, steer wrestling) may elicit an aerobic component that has not been previously considered or investigated. When considering that experience in this sport is solely achieved through grueling practices involving actual, repetitive, human versus livestock competition, practices closely imitate a sport-specific form of interval training. This may explain the higher than expectedV02 values observed in this population. Although performance decrements and the potential for injury can be related to low levels of fitness, 1,6,27 this may not be applicable to this group, since they do exhibit comparable levels of aerobic capacity to other athletes in short-burst-type activities. Regardless of the anecdotal arguments, the effect of an aerobic training program on the performance of rodeo athletes remains to be determined and is an area for future study. The typical elevated preexercise blood lactate concentrations observed in subjects may have been a result of pretest anxiety and subsequent catecholamine response often found in subjects unfamiliar with laboratory testing. Male lactate values (13.7 to 15.5 mmol/L) were similar to elite male pentathlon values and higher than levels documented in triathletes and other Olympic events.44,51 A mean lactate concentration of 11.3 mmol/L in the female group was higher than values reported in elite female distance runners, swimmers, basketball, and tennis players.51 were
Blood
chemistry
The elevated hematocrit levels ranging from 47.9% to 50.0% in the men and 44.3% in women are levels typically observed at high altitude, where these data were gathered.18 The lower
414
concentration found in the female rodeo group the male group is consistent with earlier research indicating lower hemoglobin levels in females when compared to male distance runners.&dquo; The use of hemoglobin to monitor iron status is commonly accepted in a clinical setting and has been routinely recommended in physical screening.23 Research has traditionally found iron deficiency to be prevalent in females after physical training.2,36 Although transferrin, apoferritin, and ferritin levels were not established in this study to substantiate possible iron-deficient anemia, we found no evidence of negative iron balance or subnormal hemoglobin concentration in the female group. However, testing revealed three male subjects with iron concentrations ranging from 15 to 47 mg/dL, well below accepted norms.45 Possible causes may include an inadequately balanced diet with concomitant repetitive stress encountered by male rodeo athletes in their daily practices and competition. The identification of nutritional status as a possible contributor to iron balance has recently been readdressed. 41
hemoglobin
training, from
versus
ommended. When compared to other high-collision sports, the exposure:injury ratio in rodeo is staggering.3° Results indicate, however, that reaction and movement times of both genders are consistent with earlier research.13,20,50 In summary, reaction and movement response of rodeo athletes in this sample were within normal ranges commonly observed in athletes at the collegiate level of competition.
Coronary risk Research has indicated hypertension as a major predictor of impending coronary dysfunction.35 No evidence of hypertension, pre- or postexercise, was found within this group of athletes. The mean HDL cholesterol concentration in the female group was lower than values reported in female distance runners, weight lifters, and controls,33 while the mean triglyceride concentration was higher. Yet, results elicited in this study are still considered within accepted ranges for normal female populations. 14 When analyzing the normotensive and body composition data with total cholesterol :HDL-C ratios ranging from 3.0 to 4.0 across groups, results indicate an average to low risk for coronary heart disease in this population. An additional coronary risk concern is the use of tobacco products among athletes. Studies have associated tobacco use with increased risk of oral cancer and adverse effects on the cardiovascular system.8.25 There was no reported use of cigarette smoking found in this group of subjects; however, 30% of the male subjects reported current use of smokeless tobacco or snuff. This is similar to results of Connolly et al.,’ who reported smokeless tobacco use in 34% of professional baseball players. However, the interrelations and ramifications of oral tobacco use in this group of athletes are not well known and warrant further research.
Reaction/movement time Improvements in movement response in this sport are still primarily achieved by &dquo;playing yourself into shape,&dquo; as substantiated in a recent injury study.3° There is a lack of adherence to traditionally organized conditioning/training programs similar to other sports. In lieu of training protocols that closely duplicate the biomechanical and psychological aspects of this unique sport, actual competition is primarily relied on for hand/eye response refinement. This method of
an
injury standpoint, is obviously
not
rec-
CONCLUSIONS This
study examined the physical, hematologic, and exercise response of male and female collegiate rodeo athletes. When compared to other intermittent-activity sport athletes, results indicate that competitors in this sport have similar aerobic capacities, but possess lower lean body mass and greater percent body fat. Although most college rodeo athletes do not participate in traditional college training table regimens, serum lipid profiles indicated an average to low risk for coronary heart disease. Although the effort to quantify this nontraditional sport is still in its initial stage, information concerning what the optimal aerobic capacity of rodeo athletes should be for maximal performance levels, in a basically anaerobic sport, remains unanswered. The additional health risk concerning the use of smokeless tobacco products among a small percentage of this athletic population also needs to be further investigated. Since this was a descriptive study, no direct effects of the measured variables on performance of the incidence of injuries is known, although speculation is possible. Lastly, additional development of event-specific training protocols derived from the quantitative data presented in this study may ultimately enhance athletic potential, minimize opportunity for injury and possibly provide information to coaches and allied health professionals for optimal medical care. Among the most obvious training regimens to be tested should be those of whole-body aerobic capacity and strength training.
ACKNOWLEDGMENTS This
study was funded in part by a grant from the Wrangler Corporation, Greensboro, North Carolina, and the School of Physical and Health Education, University of Wyoming, Laramie, Wyoming. REFERENCES 1. Agre JC: Hamstring injuries: Proposed aetiological factors, prevention, and treatment Sports Med 2: 21-33, 1985 2 Blum SM, Sherman AR, Boileau RA: The effects of fitness-type exercise on iron status in adult women. Am J Clin Nutr 43: 456-463, 1986 3. Brozek J, Grande F, Anderson JT, et al. Densitometric analysis of body composition. Revision of some quantitative assumptions. Ann N Y Acad Sci 110 113-140, 1963 . 4 Bruce RA Exercise testing of patients with coronary heart disease. Ann Clin Res 3: 323-332, 1971 5. Campbell DE: Maintenance of strength during a season of sports partici. 193-195, 1967 pation. Am Correct Ther J 21 6. Coleman AE: Physiological characteristics of major league baseball players.
Physician Sportsmed 10(5) . 51-57, 1982
415 7
Orleans CT, Kogan M Use of smokeless tobacco in major : 1281-1285, 1988 N Engl J Med 318 Scientific Affairs: Health effects of smokeless tobacco JAMA
Connolly GN,
league baseball
8 Council on 255 1038-1044,1986 9 Daniels J, Scardina N, Hayes J, et al: Elite and subelite female middle- and long-distance runners, in Broekhoff J, Ellis MJ, Tripps DG (eds): Sport and Elite Performers: 1984 Olympic Scientific Congress Proceedings . Champaign, IL, Human Kinetics Publishers, 1985 10. Era P, Jokela J, Heikkinen E: Reaction and movement times in men of different ages A population study Percept Mot Skills 63. 111-130, 1986 11 Fay L, Londeree BR, LaFontaine TP, et al Physiological parameters related to distance running performance in female athletes Med Sci Sports Exerc : 319-324, 1989 21 12. Fleck SJ: Body composition of elite American athletes Am J Sports Med
11: 398-403, 1983 13 Fulton CD, Hubbard AW Effect of puberty on reaction and movement times Res Q 46. 335-344, 1975 14 Gleim GW, Witman PA, Nicholas JA Indirect assessment of cardiovascular "demands" using telemetry on professional football players. Am J Sports Med 9. 178-183, 1981 15 Griffin R, Peterson KD, Halseth JR. Injuries in professional rodeo Physician
1979 et al: A natural history of athleticism and cardiovascular health JAMA 252 491-495, 1984 36 Parr RB, Bachman LA, Moss RA: Iron deficiency in female athletes 35.
Injuries in professional rodeo:
Physician Sportsmed 12(4). 81-86, 1984
250, 1985 39
An
update Physician Sportsmed 15(2) 104-115, 1987 17 Goldman HI, Becklake MR Respiratory function tests Normal values at median altitudes and the prediction of normal results. Am Rev Tuberculo Respir Dis 79 457-467, 1959 18 Guyton AC Textbook of Medical Physiology Philadelphia, WB Saunders, 1986 19 Hagerman FC, Starr LM, Murray TF: Effects of a long-term fitness program on professional baseball players Physician Sportsmed 17(4) 101-119, 1989 20 Hodgkins J Reaction time and speed of movement in males and females of various ages. Res Q 34. 335-343, 1963 21 Housh TJ, Johnson GO, Marty L, et al Isokinetic leg flexion and extension strength of university football players J Orthop Sports Phys Ther 9. 365369, 1988 Koppes G, McKiernan T, Bassan M, et al: Treadmill exercise testing part I Curr Probl Cardiol 2(8) : 26-28, 1977 23. Lampe JW, Slavin JL, Apple FS Poor iron status of women runners training for a marathon Int J Sports Med 7. 111-114, 1986 22.
24. Leon AS: Age and other predictors of coronary heart disease Med Sci Sports Exerc 19: 159-167, 1987 25 Mattson ME, Winn DM Smokeless tobacco Association with increased cancer risk NCI Monogr 8. 13-16, 1989 26 Maud PJ, Shultz BB The US national rugby team A physiological and
anthropometric assessment. Physician Sportsmed 12(9) 86-99, 1984 27 McCleod WD, Hunter SC, Etchison B Performance measurement and percent body fat in the high school athlete Am J Sports Med 11390-
397, 1983 28 McGill JC, Hall JR, Ratliff WR, et al Personality characteristics of professional rodeo cowboys J Sport Behav 9: 143-151, 1986 29. Medved R: Body height and predisposition for certain sports J Sports Med 6 89-91, 1966 30 Meyers MC, Elledge JR, Sterling JC, et al. Injuries in intercollegiate rodeo athletes Am J Sports Med 18: 87-91, 1990 31. Meyers MC, LeUnes AD, Elledge JR, et al Precompetitive mood state changes in collegiate rodeo athletes J Sport Behav 13 114-121, 1990
Paffenbarger RS, Hyde RT, Wing AL,
37 Parr RB, Hoover R, Wilmore JH, et al: Professional basketball players Athletic profiles. Physician Sportsmed 6(4) : 77-84, 1978 38 Pate RR, Barnes C, Miller W: A physiological comparison of performancematched female and male distance runners Res Q Exerc Sport 56: 245-
40
Sportsmed 11(8) 111-116, 1983 16 Griffin R, Peterson KD, Halseth JR, et al:
Meyers MC, Sterling JC, LeUnes AD: Psychological characterization of the collegiate rodeo athlete J Sport Behav 11 59-65, 1988 33 Morgan DW, Cruise RJ, Girardin BW, et al HDL-C concentrations in weight-trained, endurance-trained, and sedentary females Physician Sportsmed 14(3) : 166-181, 1986 34 Noble BJ, Maresh CM: Acute exposure of college basketball players to moderate altitude: Selected physiological response Res Q 50 668-678, 32
41
42
Pollock ML, Pels AE, Foster C, et al:
Comparison of male and female Olympic speedskating candidates, in Broekhoff J, Ellis MJ, Tripps DG 1984 (eds) Sport and Elite Performers Olympic Scientific Congress Proceedmgs Champaign, IL, Human Kinetics, 1985 Pollock ML, Schmidt DH, Jackson AS Measurement of cardio-respiratory fitness and body composition in the clinical setting Compr Ther 6 : 12-27, 1980 Raven P, Gettman L, Pollock ML A physiological evaluation of professional soccer players Br J Sports Med 10. 209-216, 1976 Rusko H, Havu M, Karvonen ME Aerobic performance capacity in athletes.
Eur J Appl Physiol 38 151-159, 1978 43 SAS User’s Guide Carey, NC, SAS Institute, 1985 44 Schneider DA, Lacroix KA, Atkinson GR, et al Ventilatory threshold and maximal oxygen uptake during cycling and running in triathletes. Med Sci Sport Exerc 22. 257-264, 1990 45 Scully RE Normal reference laboratory values. Blood, plasma or serum values. N Engl J Med 302 37-40, 1980 46 Shields CL, Whitney FE, Zomar VD Exercise performance of professional football players. Am J Sports Med 12: 455-459, 1984 47 Sigma Technical Bulletin No. 352-3. Quantitative determination of cholesterol in high density lipoprotein (HDL) fraction of serum or plasma St. Louis, Sigma Chemical Company, 1987 48 Squires RW, Bove AA Cardiovascular profiling. Clin Sports Med 3: 11-30, 1984 49 Steenkamp I, Fuller C, Graves, J, et al: Marathon running fails to influence RBC survival rates in iron-replete women Physician Sportsmed 14(5) : 89-
95, 1986 50 Thomas JR, Gallagher JD, Purvis GJ Reaction time and anticipation time: Effects of development Res Q Exerc Sport 52 : 359-367, 1981 51 Tokmakidis SP, Tsopanakis A, Tsarouchas E, et al. Physiological profile of elite athletes to maximal effort, in Broekhoff J, Ellis MJ, Tripps DG (eds) Sport and Elite Performers 1984 Olympic Scientific Congress Proceedings . Champaign, IL, Human Kinetics, 1985 52. Tuza G: Training considerations for rodeo. Natl Strength Cond Assoc J 6:
38-41,1985 53 Wilmore JH The assessment of and variation in aerobic power in world class athletes as related to specific sports Am J Sports Med 12 : 120-127, 1984 54 Wilmore JH, Haskell WL. Body composition and endurance capacity of professional football players. J Appl Physiol 33 564-567, 1972 55 Wilmore JH, Parr RB, Haskell WL, et al Football pros’ strengths and CV weakness-charted Physician Sportsmed 4(10) 44-54, 1976
performance of collegiate
rodeo
MICHAEL C. MEYERS,*† PhD, JOHN G. WILKINSON,‡ PhD, ELLEDGE,§ PhD, HOMER TOLSON,§ PhD, JAMES C. STERLING,* MD, AND J. RICHARD COAST,§ PhD
From *The Texas
Sports Science Institute, Sugar Land, Texas, the ‡School of Physical & Health Education, University of Wyoming, Laramie, Wyoming, and the §Department of Health & Physical Education, Texas A&M University, College Station, Texas
ABSTRACT
subjective analyses derived from limited measurements strength and speed. Subsequent conditioning or training programs were also modified from this original general concept. Within the last decade, a better understanding of the physiologic responses to exercise and concomitant advances in technology have generated sport-specific training and on
of
In this study we examined the physical, hematologic, and exercise response of 20 male and 10 female athletes of the National Intercollegiate Rodeo Association, Central Rocky Mountain Region. Male subjects were grouped by roughstock, steer wrestling, and roping events. Female athletes were grouped separately. Maximal aerobic capacity, pulmonary ventilation, respiratory exchange ratio, energy expenditure, maximal heart rate, blood pressure, treadmill time, pre- and postexercise lactate, percent body fat, lean body mass, blood chemistry, serum lipids, and reaction/movement time were analyzed by event. No significant differences (P > 0.05) were found in any of these categories between male events. Mean resting blood chemistry parameters of rodeo athletes were within normal ranges. Steer wrestling athletes possessed greater body size and lean body mass than other groups. When analyzing body composition, blood pressure, and total cholesterol:high-density lipoprotein (HDL) cholesterol ratios, results indicate average to low risk for coronary heart disease. When compared to other intermittent-activity sport athletes, college rodeo athletes appear to have similar aerobic capacities, but possess lower lean body mass and greater percent body fat.
rehabilitation programs for traditional athletes based on a wide array of quantitative measurements. Research on the sport of rodeo is limited. The majority of studies have primarily focused on injuries and psychologic aspects of these nontraditional competitors. 15, 16, 28,30-32 The of physiologic fitness status, the
testing, however, may identify present potential for athletic performance, the predisposition to injury, and possible coronary risk concerns and have substantial application to the understanding of this unique sport and the development of sport-specific training programs. At this time, no published studies exist that examine the exercise performance of collegiate rodeo athletes. Rodeo competition is an activity that is basically intermittent in nature, with short periods of highly intense activity. However, as in any sport, the rodeo competitor still requires an aerobic conditioning protocol. Studies have indicated that, by the end of a game, cardiovascular fitness significantly influences the onset of fatigue and the performance potential of athletes subjected to repetitive, high-intensity activity. 14 Physiologic testing of athletes has demonstrated that those athletes who exhibit low aerobic capacity and high percent body fat have a higher incidence of fatigue and show decreases in performance levels.2’ This may ultimately be viewed as a predisposition to injury,’ since injury potential is inversely associated with state of training. Although not conclusive, additional studies have indicated the potential for significant reduction in musculoskeletal injuries resulting from the identification and subsequent enhancement of use
Sports medicine specialists and coaches have continually searched for ways to identify and enhance athletic performance and minimize the risk of injury. Early characterization of athletes was not sport specific and was primarily based t Address correspondence and reprnt requests to. Michael C Meyers, PhD, The Texas Sports Science Institute, 1250 Shorelne Drme, Suite 295, Sugar Land, TX 77478 410
411
muscular strength,
flexibility, and endurance in various ath-
letes.5,21,54 While event-specific strength and conditioning protocols for rodeo have been subjectively prescribed,52 a generalized exercise prescription for the rodeo athlete would be limited without adequate physiologic data. Traditional sport studies have also indicated that physiologic characteristics of athletes varied between sports and between player position.29,44,53,55 Therefore, the purpose of this study was to describe the physical, hematologic, and exercise response of collegiate rodeo athletes in a given event and compare results to other traditional athletes.
15-second average of the data. Blood pressure was monitored at prescribed intervals from rest through the exercise bout and recovery. Venous blood samples for the determination of lactate accumulation were taken via finger sticks from each subject immediately before and after the maximal exercise tests. Blood lactate concentrations were measured in duplicate using a YSI model L23 auto analyzer (YSI Inc, Yellow Springs, OH). Height and weight were determined by calibrated scales, and body composition was determined by hydrostatic weighing techniques. Residual volume was estimated in accordance with standard procedures.&dquo; Lean body mass (LBM) and percent body fat were calculated from body density
manually
MATERIALS AND METHODS
values.’
Subjects
using a Lafayette reaction/movement timer (model 63016, Lafayette Instruments, Lafayette, IN) equipped with visual
During the 1988 and 1989 collegiate rodeo season, physiologic assessments were performed on 20 male and 10 female athletes of the National Intercollegiate Rodeo Association (NIRA), Central Rocky Mountain Region. The majority of athletes were presently or formerly high school or college champions in their respective events. These athletes initially reported to the Human Energy Research Laboratory (2200 meters above sea level) at the University of Wyoming in the morning after a 12- to 14-hour fast. Data were collected on all athletes to obtain the following information: anthropometric status and body composition, cardiovascular endurance, resting blood chemistry, postexercise blood lactate, coronary risk, and visual reaction/movement time. Each individual test battery was completed within the same day and all testing was completed within a 2-week period.
stimulus and 2 response keys.lO,46 There is substantial variation in protocols found among studies using response key testing; we chose a distance of 17 inches from start to target key to allow optimal arm movement with limited shoulder involvement. Each subject was initially given 5 visual warm1 trial), followed by 10 visual stimuli up trials (1 stimulus randomly given in time increments ranging from 1 to 4 seconds. Life-style and nutrition profiles were determined using a standard self-response, laboratory-developed questionnaire to identify coronary risk factors and dietary history of each subject. Questions pertaining to family history of injury, illness, and life-style were also included.
Data
analysis
Procedures
Data
were
Mean visual reaction and movement times were quantified
After obtaining written informed consent from both subjects and coaches, and clearance from the university human research committee, 2 X 10 ml blood samples were drawn from an antecubital vein by a certified hemotechnician and sent to a certified hospital laboratory (College of American Pathologists) for determination of blood electrolytes, cholesterol, triglyceride, glucose, and complete blood count. Serum high-density lipoprotein cholesterol concentration was analyzed in the human performance laboratory by enzymatic
technique. 41 Cardiovascular endurance was determined by having subjects complete a maximal graded exercise teSt4 on a Quinton 24-72 treadmill (Quinton Instruments, Seattle, WA) with heart rate data continually recorded and calculated using a SensorMedics Horizon electrocardiograph (SensorMedics, Anaheim, CA). Electrode lead placement was performed according to the Mason-Liker modified 12-lead system for treadmill stress testing.22 Ventilatory and metabolic variables, i.e., aerobic capacity (VOZ max), ventilation (VE max), and respiratory exchange ratio, were determined breath by breath on a SensorMedics Horizon 4400tc metabolic cart following autocalibration using gases of known concentrations. Maximal V02 and VE values were calculated from a
=
analyzed by event, with male athletes grouped by roughstock (bull riding, bareback riding, saddle bronc riding), steer wrestling, and roping events (including either calf or team roping). Female athletes participating in barrel racing, goat-tying, and break-away roping were grouped separately. Final analysis comprised four categories consisting of nine collegiate events. Test-retest reliability procedures were performed to identify possible physiologic response distortion. Pearson product-moment correlation techniques were applied to assess significant association between dependent variables. Factor analysis procedures were then used for data reduction to assess each variable’s strength of association and to obtain factor scores to use as dependent variables. This reduced the number of variables to compare for the differences between events. After the initial factor method of principal component, eigenvalues of the correlation matrix revealed that 100% of the cumulative data were contained in two factors. With additional varimax rotation and subsequent rsquared procedures, the variables of body fat and cholesterol were chosen for further analyses. Analysis of variance (ANOVA) using General Linear Model (SAS Institute Inc, Cary, NC) procedures43 only revealed significant gender differences (P < 0.05) in percent body fat. Considering the difference in physical demands between male and female events,
412
direct comparison between gender was not made. However, for descriptive purposes and comparison with traditional athletes, all data are presented.
The mean anthropometric and body composition values of collegiate rodeo athletes by event are presented in Table 1. Steer wrestlers were heavier and had more lean body mass than males in the roughstock and roping events. Roughstock were
shorter than males in the roping and steer
wrestling events. Mean exercise response of collegiate rodeo athletes by presented in Table 2. No differences in VE max, V02 max, maximal respiratory exchange ratio, energy expenditure, maximal heart rate, blood pressure or maximal time on the treadmill were found between males in the roughstock, roping, and steer wrestling events. Selected mean resting blood chemistry parameters of collegiate rodeo athletes, as shown in Table 3, were within normal ranges across all events. Among the steer wrestling group, however, values were lower across most variables when compared to the roughstock and roping groups. Mean reaction, movement, and total response times of collegiate rodeo athletes by event are shown in Table 4. No differences were found between male events. Visual reaction event is
TABLE 1 Mean
anthropometric and body composition data of collegiate rodeo athletes by event’
a Values
b
and movement
are means
± SEM.
Body composition Past studies have indicated that low percent body fat values are typically observed in athletes involved in extreme anaerobic competition. 12 Whether this is a physical requirement for success in various sports or simply because of stereotypic selection by coaches is not conclusive. The low percent fat values found among roughstock riders in this study, however, support this theory, reflecting a somatotype typically seen in this physically intensive, 8-second event. A mean body fat of 12.0% among the male subjects was lower than that reported in professional football55 and ice hockey players,42 but higher than reported percentages in professional baseball,6,19 basketball, 17 soccer,&dquo; and rugby players.&dquo; Since performance is inversely related to excess body fat,2’ the high percent body fat values observed among steer wrestlers and the female rodeo athletes, in relation to established athletic norms, pose some concern for improvements in the physical conditioning of athletes in this sport. This higher body fat among the steer wrestlers might be useful, however, when noting the nature of the event, in which a large body size and higher percent body fat may be advantageous when wrestling an animal of this size. This could be considered a similar argument to that for a higher body fat percentage in football linemen and linebackers. Steer wrestlers possessed greater body size than found among athletes in other male events that, in this study, led to a greater lean body mass. When compared to other intermittent-activity sports (Table 5), lean body mass among college rodeo competitors was lower than lean body mass found in athletes competing in football, basketball, and baseball.6,37,55
TABLE 2 Mean exercise response of collegiate rodeo athletes
° Values
msec
DISCUSSION
RESULTS
athletes
time by event ranged from 253 to 275 time from 123 to 157 msec.
are means
±
by
eventa
SEM.
RER, respiratory exchange ratio; METS,
energy
expenditure; HR,
heart rate; Tmax, treadmill time; BP, blood pressure.
413 TABLE 3 Mean
° Values
are
resting blood chemistry of collegiate rodeo athletes by event’
means ± SEM.
TABLE 4 Mean
reaction, movement, and total response time rodeo athletes by eventa
° Values
are
of collegiate
means ± SEM.
TABLE 5 Mean
physiologic comparison between male collegiate rodeo athletes and athletes in other intermittent-activity sports
° Values obtained from work done
Aerobic
on a
cycle ergometer.
capacity
When comparing maximal aerobic capacity with athletes involved in intermittent-activity sports (Table 5), male rodeo athletes exhibited V02 max values similar to elite Olympic basketball, water polo, and gymnastic athletes, and higher than values reported in weight lifters.51 These values for rodeo athletes were also similar to results reported in professional football,55 basketball,&dquo; and baseball players.6,19 As expected, when compared to high-aerobic events, both male and female rodeo subjects possessed lower V02 max and VE max than observed in middle and long-distance
runners,11 cyclists, swimmers,9~51 soccer players,41 triathletes,44 and speedskaters.39 However, because the stress tests administered to subjects in this study at 2200 meters above sea level, B702 max could be underestimated by approximately 8% as compared to sea level values.34 In addition, when resulting V02 max and energy expenditure data in this study were compared to established norms,40,48 male rodeo subjects were considered to possess above average aerobic capacity while female subjects possessed below average to average aerobic capacity. This suggests that training and competing in the male rodeo events (i.e., roughstock, roping, steer wrestling) may elicit an aerobic component that has not been previously considered or investigated. When considering that experience in this sport is solely achieved through grueling practices involving actual, repetitive, human versus livestock competition, practices closely imitate a sport-specific form of interval training. This may explain the higher than expectedV02 values observed in this population. Although performance decrements and the potential for injury can be related to low levels of fitness, 1,6,27 this may not be applicable to this group, since they do exhibit comparable levels of aerobic capacity to other athletes in short-burst-type activities. Regardless of the anecdotal arguments, the effect of an aerobic training program on the performance of rodeo athletes remains to be determined and is an area for future study. The typical elevated preexercise blood lactate concentrations observed in subjects may have been a result of pretest anxiety and subsequent catecholamine response often found in subjects unfamiliar with laboratory testing. Male lactate values (13.7 to 15.5 mmol/L) were similar to elite male pentathlon values and higher than levels documented in triathletes and other Olympic events.44,51 A mean lactate concentration of 11.3 mmol/L in the female group was higher than values reported in elite female distance runners, swimmers, basketball, and tennis players.51 were
Blood
chemistry
The elevated hematocrit levels ranging from 47.9% to 50.0% in the men and 44.3% in women are levels typically observed at high altitude, where these data were gathered.18 The lower
414
concentration found in the female rodeo group the male group is consistent with earlier research indicating lower hemoglobin levels in females when compared to male distance runners.&dquo; The use of hemoglobin to monitor iron status is commonly accepted in a clinical setting and has been routinely recommended in physical screening.23 Research has traditionally found iron deficiency to be prevalent in females after physical training.2,36 Although transferrin, apoferritin, and ferritin levels were not established in this study to substantiate possible iron-deficient anemia, we found no evidence of negative iron balance or subnormal hemoglobin concentration in the female group. However, testing revealed three male subjects with iron concentrations ranging from 15 to 47 mg/dL, well below accepted norms.45 Possible causes may include an inadequately balanced diet with concomitant repetitive stress encountered by male rodeo athletes in their daily practices and competition. The identification of nutritional status as a possible contributor to iron balance has recently been readdressed. 41
hemoglobin
training, from
versus
ommended. When compared to other high-collision sports, the exposure:injury ratio in rodeo is staggering.3° Results indicate, however, that reaction and movement times of both genders are consistent with earlier research.13,20,50 In summary, reaction and movement response of rodeo athletes in this sample were within normal ranges commonly observed in athletes at the collegiate level of competition.
Coronary risk Research has indicated hypertension as a major predictor of impending coronary dysfunction.35 No evidence of hypertension, pre- or postexercise, was found within this group of athletes. The mean HDL cholesterol concentration in the female group was lower than values reported in female distance runners, weight lifters, and controls,33 while the mean triglyceride concentration was higher. Yet, results elicited in this study are still considered within accepted ranges for normal female populations. 14 When analyzing the normotensive and body composition data with total cholesterol :HDL-C ratios ranging from 3.0 to 4.0 across groups, results indicate an average to low risk for coronary heart disease in this population. An additional coronary risk concern is the use of tobacco products among athletes. Studies have associated tobacco use with increased risk of oral cancer and adverse effects on the cardiovascular system.8.25 There was no reported use of cigarette smoking found in this group of subjects; however, 30% of the male subjects reported current use of smokeless tobacco or snuff. This is similar to results of Connolly et al.,’ who reported smokeless tobacco use in 34% of professional baseball players. However, the interrelations and ramifications of oral tobacco use in this group of athletes are not well known and warrant further research.
Reaction/movement time Improvements in movement response in this sport are still primarily achieved by &dquo;playing yourself into shape,&dquo; as substantiated in a recent injury study.3° There is a lack of adherence to traditionally organized conditioning/training programs similar to other sports. In lieu of training protocols that closely duplicate the biomechanical and psychological aspects of this unique sport, actual competition is primarily relied on for hand/eye response refinement. This method of
an
injury standpoint, is obviously
not
rec-
CONCLUSIONS This
study examined the physical, hematologic, and exercise response of male and female collegiate rodeo athletes. When compared to other intermittent-activity sport athletes, results indicate that competitors in this sport have similar aerobic capacities, but possess lower lean body mass and greater percent body fat. Although most college rodeo athletes do not participate in traditional college training table regimens, serum lipid profiles indicated an average to low risk for coronary heart disease. Although the effort to quantify this nontraditional sport is still in its initial stage, information concerning what the optimal aerobic capacity of rodeo athletes should be for maximal performance levels, in a basically anaerobic sport, remains unanswered. The additional health risk concerning the use of smokeless tobacco products among a small percentage of this athletic population also needs to be further investigated. Since this was a descriptive study, no direct effects of the measured variables on performance of the incidence of injuries is known, although speculation is possible. Lastly, additional development of event-specific training protocols derived from the quantitative data presented in this study may ultimately enhance athletic potential, minimize opportunity for injury and possibly provide information to coaches and allied health professionals for optimal medical care. Among the most obvious training regimens to be tested should be those of whole-body aerobic capacity and strength training.
ACKNOWLEDGMENTS This
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