Tight Ends Research Articles

Core Temperatures In NFL Players

Heat stroke deaths in football (FB) players usually occur during the first 3 days of pre-season practices. Experimental studies show that maximal core temperatures (Tc max) decline in subjects in response to the physiological adaptations associated with acclimatization. Using ingestible sensors that allow accurate measurements of Tc during exercise, we recently recorded Tc in National Football League (NFL) players during pre-season practices and compared the Tc response of large interior linemen to those of smaller backs and receivers. However, we are not aware of field study comparing the Tc responses of the same NFL players during the first few days of pre-season practice versus practices on the 10th day. PURPOSE To measure Tc in professional FB players and compare the Tc max reached on the 2nd or 3rd day (day 2/3) of practice to those obtained on the 10th day. METHODS Eight NFL first or second team players, age = 26.1 ± 3.3 yr, height = 188.9 ± 5.9 cm, mass = 120.2 ± 24.4 kg, body surface area (BSA) = 2.45 ± 0.23 m2 and BSA/mass = 0.0197 ± 0.0014 m2 kg−1, representing the following positions; wide receiver, corner back, tight ends, linebacker, defensive and offensive linemen participated. Subjects ingested a temperature sensor at 11:00 PM prior to, or in the morning of the days of data collection during preseason training camp. Subjects' resting Tc were recorded in an air-conditioned area 1 h prior to and then approximately every 12 min during two h of practice in full football equipment. Tc was also measured during the afternoon practices with players dressed in a helmet, shorts and shell. Body weight was recorded before and after practices for determination of percent dehydration (%Dehy). ΔTc over time were analyzed using repeated measures ANOVA and differences in Tc max and %Dehy on days 2/3 versus day 10 were analyzed using correlated t-tests. RESULTS Wet bulb globe temperatures ranged from 23.7 to 29 °C on days 2/3, and 20.4 to 27.2 °C on day 10. A significant linear trend was found for Tc on days 2/3 and day 10, p<0.01. When the highest Tc recorded in each subject were compared, Tc max were higher on days 2/3 (39.1 ± 0.6 °C, range = 38.3 to 40.9 °C) compared to day 10 (38.3 ± 0.4 °C, range = 37.6 to 39.4 °C), p<0.001. There were no differences in %Dehy on days 2/3 (−1.26 ± 1.1%) versus day 10 (−1.25 ± 0.87). No correlations were found between the players' Tc max and %Dehy. CONCLUSIONS NFL players reached higher Tc during the first few days of preseason practices compared to day 10. The highest Tc in all FB was generally obtained during live scrimmaging. %Dehy on days 2 or 3 was not different from day 10 and was not associated with Tc max. Supported by a faculty development grant from West Chester University.

Core Temperatures In NFL Players

Heat stroke deaths in football (FB) players usually occur during the first 3 days of pre-season practices. Experimental studies show that maximal core temperatures (Tc max) decline in subjects in response to the physiological adaptations associated with acclimatization. Using ingestible sensors that allow accurate measurements of Tc during exercise, we recently recorded Tc in National Football League (NFL) players during pre-season practices and compared the Tc response of large interior linemen to those of smaller backs and receivers. However, we are not aware of field study comparing the Tc responses of the same NFL players during the first few days of pre-season practice versus practices on the 10th day. PURPOSE To measure Tc in professional FB players and compare the Tc max reached on the 2nd or 3rd day (day 2/3) of practice to those obtained on the 10th day. METHODS Eight NFL first or second team players, age = 26.1 ± 3.3 yr, height = 188.9 ± 5.9 cm, mass = 120.2 ± 24.4 kg, body surface area (BSA) = 2.45 ± 0.23 m2 and BSA/mass = 0.0197 ± 0.0014 m2 kg−1, representing the following positions; wide receiver, corner back, tight ends, linebacker, defensive and offensive linemen participated. Subjects ingested a temperature sensor at 11:00 PM prior to, or in the morning of the days of data collection during preseason training camp. Subjects' resting Tc were recorded in an air-conditioned area 1 h prior to and then approximately every 12 min during two h of practice in full football equipment. Tc was also measured during the afternoon practices with players dressed in a helmet, shorts and shell. Body weight was recorded before and after practices for determination of percent dehydration (%Dehy). ΔTc over time were analyzed using repeated measures ANOVA and differences in Tc max and %Dehy on days 2/3 versus day 10 were analyzed using correlated t-tests. RESULTS Wet bulb globe temperatures ranged from 23.7 to 29 °C on days 2/3, and 20.4 to 27.2 °C on day 10. A significant linear trend was found for Tc on days 2/3 and day 10, p<0.01. When the highest Tc recorded in each subject were compared, Tc max were higher on days 2/3 (39.1 ± 0.6 °C, range = 38.3 to 40.9 °C) compared to day 10 (38.3 ± 0.4 °C, range = 37.6 to 39.4 °C), p<0.001. There were no differences in %Dehy on days 2/3 (−1.26 ± 1.1%) versus day 10 (−1.25 ± 0.87). No correlations were found between the players' Tc max and %Dehy. CONCLUSIONS NFL players reached higher Tc during the first few days of preseason practices compared to day 10. The highest Tc in all FB was generally obtained during live scrimmaging. %Dehy on days 2 or 3 was not different from day 10 and was not associated with Tc max. Supported by a faculty development grant from West Chester University.

Body Size and Composition of National Football League Players

The purpose of this study was to present a profile of body size and composition of National Football League (NFL) players prior to the start of the regular season. Fifty-three members of the Indianapolis Colts professional football team were measured for height, body mass, and percentage body fat using the BOD POD air-displacement plethysmography system during summer camp of the 2003 football season. These data were categorized by position for comparison with previous studies of NFL football players. The relationships observed were as follows (= represents nonsignificant; > represents p < or = 0.05): Height: Offensive Line = Defensive Line = Quarterbacks/Kickers/Punters = Tight Ends > Linebackers > Running Backs = Wide Receivers = Defensive Backs. Body Mass: Offensive Line = Defensive Line > Tight Ends = Linebackers > Running Backs = Quarterbacks/ Kickers/Punters > Wide Receivers = Defensive Backs. Percentage Body Fat: Offensive Line > Defensive Line > Quarterbacks/ Kickers/Punters = Linebackers = Tight Ends > Running Backs = Wide Receivers = Defensive Backs. Comparisons to teams in the 1970s indicate that body mass has increased only for offensive and defensive linemen; however, height and body fat among player positions have not dramatically changed. Furthermore, the body mass index is not an accurate measure or representation of body fat or obesity in NFL players. These data provide a basic template for size profiles and differences among various positions and allow comparisons with other studies for changes in the NFL over the past 3 decades.

Concussion in professional football: repeat injuries--part 4.

A 6-year study was conducted to determine the signs, symptoms, and management of repeat concussion in National Football League players. From 1996 to 2001, concussions were reported by 30 National Football League teams using a standardized reporting form filled out by team physicians with input from athletic trainers. Signs and symptoms were grouped by general symptoms, somatic complaints, cranial nerve effects, cognition problems, memory problems, and unconsciousness. Medical actions taken and management were recorded. Data were captured for 887 concussions in practices and games involving 650 players. A total of 160 players experienced repeat injury, with 51 having three or more concussions during the study period. The median time between injuries was 374.5 days, with only six concussions occurring within 2 weeks of the initial injury. Repeat concussions were more prevalent in the secondary (16.9%), the kick unit on special teams (16.3%), and wide receivers (12.5%). The ball return carrier on special teams (odds ratio [OR] = 2.08, P = not significant) and quarterbacks (OR = 1.92, P < 0.1) had elevated odds for repeat injury, followed by the tight end (OR = 1.24, P = not significant) and linebackers (OR = 1.22, P = not significant). There were similar signs and symptoms with single and repeat concussion, except for a higher prevalence of somatic complaints in players on their repeat concussions compared with their first concussion (27.5% versus 18.8%, P < 0.05). More than 90% of players were managed by rest, and 57.5% of those with second injuries returned to play within a day. Players with three or more concussions had signs, symptoms, and treatment similar to those with only a single injury. The most vulnerable players for repeat concussion in professional football are the ball return carrier on special teams and quarterbacks. Single and repeat concussions are managed conservatively with rest, and most players return quickly to play.

Core Temperature in Professional Football Players during practice

0369 Heat related deaths have been documented in football players at all levels of competition. Ingestible temperature sensors now allow accurate measurements of core temperature (Tc) in these athletes while they participate in football activity. Core temperatures of professional players in the National Football League (NFL) while they participate in football practice have never been reported. PURPOSE: To measure the rise in Tc during practice in professional football players and compare the Tc of larger interior lineman (LM) to those of backs and receivers (BKS). METHODS: Eight LM, age = 26.5 ± 2 yr, height = 191.8 ± 4.5 cm, body weight (BW) = 134.8 ± 10.7 kg and body surface area (BSA) = 2.61 ± 0.12 m2 and six BKS (wide receivers, half backs, defensive backs, tight ends) age = 27 ± 4.2 yr, height = 185 ± 6.3 cm, BW = 95.6 ± 11.1 kg and BSA = 2.19 ± 0.16 m2 participated in the study. All players were NFL first or second team veterans. Subjects ingested a sensor at 11:00 PM prior to the day of data collection during pre-season training camp in July. Resting Tc were recorded in an air-conditioned area 1 h prior to the morning practice. Tc was then recorded in each player approximately every 15 min during two hours of football practice in full equipment. The practice consisted of three distinct periods including individual drills, 7 on 7 team and live scrimmage. Tc was also measured during the afternoon practice in shells. BW was recorded before and after practices for determination of percent dehydration. Changes in Tc over time were analyzed using repeated measures ANOVA and group differences in Tc and percent dehydration were analyzed using independent t-tests. RESULTS: The highest wet bulb temperatures were 22.8°C and 20.6°C during the morning and afternoon practices, respectively. Height (p < 0.05), BW (p < 0.0001) and BSA (p < 0.001) were all higher in LM compared to BKS. A significant linear trend was found for Tc in both groups, p < 0.0001. During the AM practice Tc rose from 37.07 ± 0.13 °C to 38.81 ± 0.48 °C in LM and 36.99 ± 0.09 °C to 38.36 ± 0.44 °C in BKS. When the highest two Tc recorded in each subject were compared, Tc were higher in LM (38.65 ± 0.48 °C, range = 37.47 to 39.29 °C) than BKS (38.44 ± 0.32 °C, range = 37.81 to 39.08 °C). As measured by change in BW during practice the LM were less dehydrated compared to BKS (−0.94 ± 0.6 % versus −1.3 ± 0.7 %), p < 0.05. CONCLUSIONS: NFL LM reached higher Tc during football practice compared to smaller BKS. The highest Tc in all subjects were generally obtained during live scrimmaging. Level of dehydration as measured by BW loss was not associated with Tc. LM had higher Tc but were less dehydrated compared to BKS. Supported by a faculty development grant from West Chester University.

COMPARISON OF PHYSICAL AND PERFORMANCE CHARACTERISTICS OF NCAA DIVISION I FOOTBALL PLAYERS

The purpose of this study was to compare normative data from present Division I National Collegiate Athletic Association football teams to those from 1987. Players were divided into 8 positions for comparisons: quarterbacks (QB), running backs (RB), receivers (WR), tight ends (TE), offensive linemen (OL), defensive linemen (DL), linebackers (LB), and defensive backs (DB). Comparisons included height, body mass, bench press and squat strength, vertical jump, vertical jump power, 40-yd-dash speed, and body composition. Independent t-tests were used to analyze the data with level of significance set at p < 0.01. Significant differences (p < 0.01) were found in 50 of 88 comparisons. From 1987 until 2000, Division I college football players in general have become bigger, stronger, faster, and more powerful. Further research is warranted to investigate if these trends will continue.

Shoulder Injury ??? Football

0413 HISTORY: A 20-year-old Division 1 football tight end sustained a left shoulder injury while being tackled after a completed pass. Midway through practice, during football preseason, after catching a pass he was tackled by the defensive end. With his arms holding the ball, his shoulder adducted and his elbow at 90 degrees flexion, he sustained direct trauma to the superior-anterior aspect of the left shoulder upon impact to the grass field. He experienced severe left shoulder pain and immediately reported his symptoms to the athletic trainer. PHYSICAL EXAMINATION: Examination of the left shoulder on the sidelines revealed a dramatic prominence of the distal tip of the clavicle, and a significant shoulder droop. There was obvious tenting of the skin. There was significant tenderness over the acromio-clavicular (AC) joint area, and along the deltoid and trapezius. He was unable to perform cross-arm adduction secondary to pain. The distal end of the clavicle was strikingly hypermobile, and did not reduce with shoulder shrugging. There was a decrease in range of motion noted in all planes secondary to pain. Sensation was intact and peripheral pulses were normal. DIFFERENTIAL DIAGNOSIS: Acromioclavicular Dislocation – Type 3 Acromioclavicular Dislocation – Type 4 Acromioclavicular Dislocation – Type 5 Clavicular fracture TEST AND RESULTS: Left shoulder anterior-posterior (AP) radiograph: superiorly displaced clavicle coracoclavicular distance = 4.0 cm no fracture Left Shoulder axillary radiograph: Clavicle displaced posteriorly 2.0 cm FINAL/WORKING DIAGNOSIS: Acromioclavicular Dislocation – Type 5 TREATMENT AND OUTCOMES: Iced and immobilized with sling immediately post-injury. Surgical repair 5 days post-injury revealed that the clavicle was embedded into the trapezius muscle. The AC joint was reduced and the coracoclavicular ligaments were reconstructed with a gracilis tendon autograft from the left leg and reinforced with fiber wire. Supine rehab began 2 days post-op with left upper extremity isometrics through week 1, rhythmic stabilization added in week 2, and manual resistance within his range of motion added in week 3. Standing rehab began in week 4 with dynamic range of motion and strengthening exercises, followed by the addition of plyometrics and light weight room training in week 5. Follow-up AP radiograph 6 weeks post-repair showed a coracoclavicular distance of 1.3 cm. Light contact football practice began 6 weeks post-repair. Returned to full contact football 7 weeks post injury when he had full, painless ROM, and normal strength.

Exit Discrimination in the NBA: A Duration Analysis of Career Length

Using a panel study of annual NBA data (1989–99) we do not find evidence of exit discrimination on career length in the NBA. This result is inconsistent with results from data in the 1980s but is consistent with more recent findings that have measured wage discrimination in sports in the 1990s. In our semiparametric duration analysis, we find that performance variables are important in determining career length. These results suggest that team owners in the pursuit of championships keep talented players regardless of race. This is an affirmation of Becker's theoretical implications of market competition on discrimination. (JEL J71, J23)

Concussion in professional football: epidemiological features of game injuries and review of the literature--part 3.

A 6-year study was performed to determine the circumstances, causes, and outcomes of concussions in the National Football League. Between 1996 and 2001, the epidemiological features of concussions were recorded by National Football League teams with a standardized reporting form. Symptoms were reported and grouped as general symptoms, cranial nerve symptoms, memory or cognitive problems, somatic complaints, and loss of consciousness. The medical actions taken were recorded. In total, 787 game-related cases were reported, with information on the players involved, type of helmet impact, symptoms, medical actions, and days lost. Concussion risks were calculated according to player game positions. There were 0.41 concussions per National Football League game. The relative risk was highest for quarterbacks (1.62 concussions/100 game-positions), followed by wide receivers (1.23 concussions/100 game-positions), tight ends (0.94 concussion/100 game-positions), and defensive secondaries (0.93 concussion/100 game-positions). The majority of concussions (67.7%) involved impact by another player's helmet. The remainder involved impact by other body regions of the striking player (20.9%) or ground contact (11.4%). The three most common symptoms of mild traumatic brain injury were headaches (55.0%), dizziness (41.8%), and blurred vision (16.3%). The most common signs noted in physical examinations were problems with immediate recall (25.5%), retrograde amnesia (18.0%), and information-processing problems (17.5%). In 58 of the reported cases (9.3%), the players lost consciousness; 19 players (2.4%) were hospitalized. A total of 92% of concussed players returned to practice in less than 7 days, but that value decreased to 69% with unconsciousness. The professional football players most vulnerable to concussions are quarterbacks, wide receivers, and defensive secondaries. Concussions involved 2.74 symptoms/injury, and players were generally removed from the game. More than one-half of the players returned to play within 1 day, and symptoms resolved in a short time in the vast majority of cases.

Body Composition in Division I Football Players

This study assessed body composition of Division I football players (n = 69) and compared the findings with previously reported data to ascertain whether the increase in player total body mass that has been observed over the past 10 years has been accompanied by an increase in body fat. Body composition was determined by hydrostatic weighing and the measurement of skinfold thicknesses. Total body mass, skin-fold thicknesses, and body fat were greater in the current players than in players in studies conducted in the early 1980s and early 1990s. Body fat varied significantly across playing position, with the defensive backs, offensive backs, and receivers being the leanest and the offensive linemen and tight ends the most fat. There was no significant relationship between body composition and playing year or scholarship status, nor were any differences observed between ethnic groups. Of important clinical relevance was the finding that the linemen (offensive, defensive) and tight ends were on average greater than 25% body fat, the borderline for obesity in this age group. Much of this fat was deposited in the abdominal region, a significant finding when one considers the high correlation between abdominal obesity and ischemic heart disease and stroke. The current findings suggest that more attention needs to be given to the nature of the increase in body mass being achieved by today's football player to minimize long-term negative health consequences, and the findings reemphasize the need identified in earlier studies of the importance of detraining programs for these athletes.

Peak Flow Measurements in Professional Football Players

Introduction: At training camp for the 1996 NFL Philadelphia Eagles, there was an athlete who suffered acute reactive airway disease. Peak flow measurements at the time of acute exacerbation and obvious respiratory distress were notable for being over 600, well within the normal range for this player's height and age. An extensive review of the literature revealed no prior published reports of peak flow measurements of professional football players in the United States. Watson describes pulmonary function in Irish soccer players, and Van Handel, et al. Studied pulmonary function in Olympic athletes. The purpose of this study was to determine the normative values of peak flow and pulmonary function tests in a population of NFL players, and to determine the difference, if any, with standard values. The corollary clinical aspect is that if the normative values are different, are we missing RAD in the population? Methods: The population is NFL Philadelphia Eagles 1996 entire roster, 70 players. Hand held peak flow measurements x 3 were recorded and pulmonary function measurements (FEV1, FVC, FEV1/FVC, FEF25-75, PEFR) using the same machine by Respi-Tech and the same technician were recorded. Predicted and percent predicted were derived based on the standard equation using sex, age and height. Mean values were determined for this population (minus the seven players with history of RAD). Body mass index and peak flow measurements and pulmonary function tests were analyzed by Pearson correlation analysis for statistical significance. A prior study by Gary and McShane showed that the players could be divided into three groups by BMI: quarterbacks, running backs and cornerbacks (herein, “SKILL”); tight ends, defensive ends, and linebackers (herein, “LB/TE”); and offensive and defensive linemen (herein, “LINE”). Mean values of peak flows by these positions were also determined and analyzed for statistical significance. Results:TableBy Pearson correlation analysis, an inverse linear relation was found between BMI and FEV1/FVC with p < .05. No other statistically significant correlation between BMI and FEV1, FVC, FEF25-75, PEFR, or hand held peak flow measurements were found.TableThere was no statistical significant relationship between position grouping and pulmonary function as determined by Pearson correlation analysis. Discussion: Despite the large height and athletic prowess of this population, their peak flow measurements were not different than normative values. Actually, all of the percent predicted values were less than 100%. Should we determine norms for this unique population by testing more athletes of this size? Perhaps standard pulmonary function equations can not apply to this population and new equations need to be derived. There were differences in pulmonary function based on position grouping by BMI, however it was not statistically significant. Since there are few measures of “fitness” in elite athletes, could pulmonary function be a measure. In this specific athletic group this may have an impact on recruiting US football players at many levels.

The Effects of Training History, Player Position, and Body Composition on Exercise Performance in Collegiate Football Players

Performance data for 261 NCAA Division 1A collegiate football players were analyzed to determine if player position, body weight, body fat, and training time were correlated with changes in performance in the following events: power clean (PC), bench press (BP), squat (SQ), vertical jump (VJ), 40-yd dash (40yd), and 20-yd shuttle (20yd). Individual positions were combined into the following groups: (A) wide receivers, defensive backs, and running backs, (B) linebackers, kickers, tight ends, quarterbacks, and specialists, and (C) linemen. Increases in body weight were positively correlated with increases in BP and PC performance for all groups. Increases in body fat were negatively correlated with performance in the PC and VJ for all groups. For group C, increases in body fat were also negatively correlated with performance in the 40yd and 20yd. Group and training time exhibited no linear relationship with performance in any of the tested events. No linear relationships were observed between the independent variables and performance in the SQ. When individual training data were analyzed longitudinally, a nonlinear increase in performance in the PC, BP, and SQ was observed as training time increased, with the greatest rate of change occurring between the first and second semesters of training.

CHANGES IN BODY SIZE OF OFFENSIVE PLAYERS IN THE NATIONAL FOOTBALL LEAGUE: A 76 YEAR REVIEW OF 27,744 PLAYERS

1359 We evaluated change in body mass (BM) and stature (S) in 51,333 National Football League (NFL) players from it's inception in 1920 through 1966. Data came from official 1920-1996 NFL rosters ( Sports Encyclopedia, 1982, 1987) and Official NFL League Records and Facts Book, 1988-1996, Workman Publishing). The comparisons focuse on offensive lineman and tight ends (OL: N=13,528) and skill position players (SPP: QB's, receivers, run backs; N=14,216). The data represent all OL and SPP players from each NFL team. The insert figures show BM and S every 5-y from 1920-1960 and yearly thereafter.FigureResults: BM of SPP increased 10% from 1920 (85.5 kg) to 1996(94,0 kg), while BM for OL increased 53% over the same period (85.5 kg to 130.8 kg). In 1920, OL and SPP weighed the same. From 1980, the rate of increase in BM differed from the rate in 1920-1935, 1935-1965, and 1965-1980 (P<0.05). S for SPP peaked in 1979 (184.5 cm), but only rose 1.8% from 1920 to 1996. For OL, S increased 8.1% from 1920 (179.2 cm), achieving stability from 1985 to 1996 (193.5 cm). From 1920 to 1996, Body Mass Index (BMI) increased 6.2% for SPP (26.2 to 27.9) and 31.1% for OL (26.6 to 34.9 kg/m2). Conclusions: Over 76 y, BM increased 0.6 kg/y for OL while stabilizing for SPP. The 0.19 cm/y increase in S means that by 2007, OL should attain 195.5 cm (6 ft 8 in) and weigh 136.1 kg (300 lb). Unfortuneatley, a BMI=35.6 kg/m2 would clasify them as high disease risk.

Trading Off: A Memoir

TRADING OFF: A MEMOIR / Michael Steinberg "Only a chUd expects justice." —Gore Vidal JACK KERCHMAN, MY OLD high school baseball coach, was a classic baU-buster, a lot Uke those Marine D.I.'s you see in oíd World War II movies. A Jew himself, "Mr. K" had a reputation for hazing the Jewish players that he thought were too soft. One of them was me. I started hearing stories about Mr. K in the mid-fifties, when I was in junior high. In three years at the high school, his footbaU teams won Queens (borough) championships, and the basebaU team got as far as the dty championship semi-finals. People in the Rockaways—neighborhood kids, parents, local merchants—began to take notice. Winning teams and wars have a way of galvanizing a neighborhood, especiaUy in New York, where everything is measured and articulated in terms of "turf." According to the buzz on the playgrounds Mr. K was an obsessed man. Max Weinstein, a tight end on the footbaU team, told us about the impassioned locker room speeches. Before each new season, Kerchman would gather the team around him in the boys' shower and reminisce about his old coUege days at Syracuse, where he was a one-hundred-sixty-pound offensive guard and defensive nose tackle for coach Biggie Munn. He proudly revealed how after the war he'd had a tryout with the New York Giants and had made it to the last cut. He always finished up by saying that he did it aU "on a Uttle talent, a big heart, and a whole lot of guts." A Jew from the roughest part of the lower East Side, Mr. K beUeved that young Jewish boys, espedaUy those from my suburban neighborhood, were "candy-asses" and quitters. At footbaU tryouts he talked about the time he Uberated a concentration camp at the end of World War II, and of how important it was for the next generation of Jews to "toughen up." So at the first scrimmage of each new season, he made the Jewish boys play without equipment. And if you were Jewish and you wanted to pitch for the basebaU team, you had to show him you could brush hitters back by throwing at their heads. The rumors were enough to convince Ritchie Zeitler and Bobby Brower, the two best athletes in our neighborhood, to transfer 136 · The Missouri Review to a local prep school. The stories frightened and fascinated me. But I knew Td be trying out for the high school basebaU team next year and I wanted to see this Kerchman character in action, so in September of my last year in junior high, I coUared Mike Rubin and Barry Aronowsky, two of my summer league basebaU buddies, and off we went to the first Saturday home footbaU game. Outside the high school field, the street hawkers sold hot dogs and popcorn, along with Rockaway High pennants, pom-poms, and trinkets. In the bleachers, students and parents chanted, "Let's go Seahorses! Seahorses, let's go!" The cheerleaders bounced up and down in their red-and-blue sweaters and short, pleated skirts, as the football team ran out on the field. Most of the players were only a few years older than me, but in their scarlet helmets and fuU gear they looked Uke Roman gladiators. As I scanned the field, I saw the pitcher's mound to the right of the south goalposts. For a long, slow moment, I floated free of the razzmatazz whUe I imagined myself standing on that mound in a Rockaway basebaU uniform. My parents, kid brother, and friends were aU in the stands, and the cheerleaders were chanting my name as I went into my wind-up and got ready to snap off a sharp, dipping curve baU. Then I spotted Kerchman standing in front of the team bench. He was in his late thirties, maybe five eight, heavyset, wearing a chocolate-brown porkpie hat and rumpled tweed topcoat. You could hear him yeUing above the crowd noise. Sometimes he'd hurl his hat to the ground and scream obscenities at a player who screwed up. He reacted...

Medial collateral ligament knee sprains in college football. Effectiveness of preventive braces.

This is the second of 2 articles on a 3-year investigation of medial collateral ligament sprains of the knee to assess the effectiveness of prophylactic knee braces in NCAA Division I college football players. Position, string, type of session, and daily brace wear were recorded. The injury rates for braced and unbraced knees were used to create an incidence density ratio. The data were stratified and simultaneously controlled for position, string, and session and evaluated for their statistical significance. The 987 Big Ten players generated 155,772 knee exposures over the study period (50% braced). Noticeable differences existed in the rates of injury for the braced and unbraced knees in almost every position during practices, depending on player or nonplayer status. When the influential factors of position, string, and session are considered, there is a consistent but not statistically significant tendency for the players wearing preventive knee braces to experience a lower injury rate than for their unbraced counterparts. For starters and substitutes in the line positions, as well as the linebackers and tight ends, there was a consistent trend toward a lower injury rate in both practices and games. The braced players in the skill positions (backs/kickers), at least during games, exhibited a higher injury rate.

Analysis of Hydrostatic Journal Bearings With End Seals

An approximate analysis for the pressure field and dynamic force coefficients in turbulent flow, centered hydrostatic journal bearings (HJBs) with fluid inertia and liquid compressibility effects is presented. Results from the analysis show that HJBs with end seals have increased damping, better dynamic stability characteristics, as well as lower flow rates, than conventional HJBs. However, hydrostatic (direct) stiffness may be lost if excessively tight end seals are used. End seals are shown to compensate for the effect of liquid compressibility within the recess volume, and prescribe a net reduction in the whirl frequency ratio for hybrid operation. Hydrostatic squeeze film dampers (HSFD) with end seals are shown to be a viable alternative in applications where a tight control of the bearing leakage is important such as in jet-engines. Furthermore, HSFDs with end seals could be used as an active device to control the available damping in a typical application.

The Development of Response Selection Accuracy in a Football Linebacker Using Video Training

This study was undertaken to determine if response selection accuracy could be improved without sacrificing a football linebacker’s response selection speed by practicing his response selection skills in relation to various offensive plays that were seen via a videotape from a viewing angle similar to what he would see in a game. The task required the linebacker to respond to the cues of the tight end and backfield play by manipulating a joystick as accurately and quickly as possible. The data revealed that there was an improvement in response selection accuracy without sacrificing response selection speed. This finding was interpreted as evidence that training using a video-tape that displays a view of plays that is similar to what is seen in a game situation can be an effective method for improving the perceptual skills needed for response selection accuracy by a linebacker in a laboratory setting.

Prophylactic knee bracing in college football.

American football can be harmful to knees. In an attempt to reduce the number and severity of knee injuries, the intercollegiate football team at the University of Arizona (Pacific Ten Conference) has been using protective braces since 1981. Objective evaluation of the effectiveness of this program is the purpose of this study. All linemen, offensive and defensive, as well as linebackers and tight ends were considered to be the players at greatest risk and were required to use the braces. The brace used was the Anderson Knee Stabler. Each player at each practice session or game was counted as one exposure. During the 4 years of brace use, there were 28,191 exposures, while the control group numbered 29,293 exposures. The data were analyzed from the perspectives of days lost from practice or games, player's position, the type and severity of injury, and the rate of injury per 100 players per season. Players at risk showed no trend to change in injury rate. Of the players at risk, the type and severity of injury in nonbraced and in braced groups were similar. A significant finding in players at risk was a two-fold increase in knee ligament injury rate per 100 players when compared to rates for an entire team. The number of season-ending injuries remained unchanged. Practice time missed for third-degree medial ligament, and for medial meniscus injuries, was significantly lower in the braced group, but this was due to improved treatment techniques initiated in 1981. Seven NCAA rule changes, directed at reducing knee injuries, have been introduced since 1981.(ABSTRACT TRUNCATED AT 250 WORDS)

Exercise performance of professional football players.

With the likely hypothesis that the degree to which a football player is physically suited to his position will determine his value as a player, we attempted to describe the characteristics of a given player and position and, from that, to determine the characteristics that make up a first class player in that position. Over a 4-year period 167 football players were examined at the National Athletic Health Institute, Inglewood, California, and grouped according to playing position and class. Position groups were: 1, linemen; 2, linebackers and tight ends; 3, running backs, quarterbacks and kickers; and 4, wide receivers and defensive backs. Classes were: I, rookies (nonstarters); II, veterans (nonstarters); and III, starters (veterans and an occasional rookie). Testing was in two phases, body characteristics and direct measurement of body function. All testing was done in connection with the preseason physical exam. Significant differences were found when data were analyzed by position. Position 1 players were taller, heavier, and had a higher percentage of body fat than players at other positions. These values decreased from Position 1 to Position 4. In terms of cardiovascular fitness the opposite trend was seen. Strength measures were also specific to given position groups. While few differences were seen when data were analyzed by class, one interesting finding was that Class III players (starters) were not only the oldest, but also had the highest level of cardiovascular fitness. Our conclusion is that while size, strength, and endurance are obvious advantages for the successful regular player, there is an unmeasurable quality reflected in the playing ability of the veteran player that is not easily identified in the beginning player.

Norms for High School Football Players Derived from Cybex Data Reduction Computer

Three hundred and forty-two male high school football players, ranging in age from 15 to 17, were screened for muscular imbalances and joint abnormalities about the knee using a Cybex II lsokinetic Dynamometer and Cybex Data Reduction Computer. Each player was tested at speeds of 60, 240, 300 degrees , and 300" per second for muscular work. The athletes were classified by position (quarterback, runningback, tight end, wide receiver, linemen, linebacker, and defensive back). Several parameters were reported: peak torque with gravity effect for both extensors and flexors, peak torque to body weight, opposing muscle group ratios, torque acceleration energy, work over a preselected number of repetitions, endurance ratio, and agonist-antagonist work ratios. The purpose of the screening was to provide data beneficial for the prevention of injury from muscular imbalance and joint instability, data useful as clinical guidelines for rehabilitation and return to play, and suggestions for strength training programs. Previous articles have been published showing peak torque, and quadriceps and hamstring ratios, as a means of preventing injury due to muscular imbalance. However, until the introduction of the Cybex(R) Data Reduction Computer, authors had no way of taking the effect of gravity on the lower limb into consideration when presenting their findings. Hamstring-quadricep ratios, once thought to be ideal at 60% or better at 60 degrees per second are now better set at 50 to 55% with gravity effect at 60 per second. The intent of this paper is not to draw any specific conclusions but to present meaningful data for the purpose of preseason screening to prevent injuries and to aid in strength-training programs.J Orthop Sports Phys Ther 1984;5(5):243-245.