Tennis| Shoulder Injuries
September 6, 2008 12:27 amSaturday, September 06, 2008
The mechanism of the overhead action in throwing sports and tennis has been studied extensively. This motion is unnatural and highly dynamic, often exceeding the physiological limits of the joint. Owing to overload of various anatomical structures, the shoulder is susceptible to injury. Optimal shoulder function requires good kinetic chain function, optimal stability, and coordination of the scapula in the overhead action. A well balanced action of the rotator cuff muscles and capsular structures is necessary to obtain a stable centre of rotation during the overhead action. (van der Hoeven H. Kibler WB. Shoulder injuries in tennis players. British Journal of Sports Medicine. 40(5):435-40; 2006 May).
Primary risk factor for glenohumeral joint injuries in overhead activity athletes is the imbalance of the external rotator cuff muscles which must contract eccentrically (lengthening contractions) while the internal rotator cuff muscles contract concentrically (shortening contractions). To reduce such injuries to tennis players, upper extremity strength training program must include increasing the eccentric external rotator cuff total exercise capacity without a subsequent increase in the concentric internal rotator total exercise capacity. (Niederbracht Y. Shim AL. Sloniger MA. Paternostro-Bayles M. Short TH. Effects of a shoulder injury prevention strength training program on eccentric external rotator muscle strength and glenohumeral joint imbalance in female overhead activity athletes. Journal of Strength & Conditioning Research. 22(1):140-5, 2008 Jan).
A study was performed to broaden the understanding of muscle function during the tennis volley under different ball placement and speed conditions by examining the activity of selected superficial muscles of the stroking arm and shoulder (flexor carpi radialis, extensor carpi radialis, triceps brachii, deltoids, and pectoralis major) and muscles related to postural support (left and right external oblique, lumbar erector spinae, and gastrocnemius) during the volley. In general, muscle activity increased with increasing ball speed. The extensor carpi radialis was more active than the flexor carpi radialis during both forehand and backhand volleys, suggesting the importance of wrist extension/abduction and grip strength. The increase in EMG levels in the forearm muscles shortly before the ball impact indicated that the subjects did not tighten their grip and wrist until moments before ball impact. Both antero-middle and postero-middle deltoids were active in most stroke phases. However, the roles of the deltoid muscles during a volley cannot be determined without knowing the actions of the other shoulder joint muscles. (Chow JW. Carlton LG. Lim YT. Shim JH. Chae WS. Kuenster AF. Muscle activation during the tennis volley. Medicine & Science in Sports & Exercise. 31(6):846-54, 1999).
Pain| Computers| Mobile Phones
September 1, 2008 1:23 pmMonday, September 01, 2008
Computer use can give rise to repetitive strain injuries with resultant pain in the neck, arms, shoulders, forearms, wrists and hands. Additionally, more people are using video games and small keyboards associated with hand-held phone devices that can give rise to pain in the fingers, especially the thumbs, from constant texting.
This following cross-sectional study evaluated the presence of pain and musculoskeletal pain syndromes in 791 adolescents to associate them to computer and video game use. The research included a questionnaire and physical examination of the musculoskeletal system. A computer was used by 99% and video games by 58%. Pain was reported by 312 (39.4%) students: 23% complained of back pain, 9% of upper limb pain, 4% of diffuse pain and 4% of pain in the trapezius muscle. A clinical examination was carried out in 359 students, and one or more musculoskeletal pain syndromes were present in 56 students (15.6%): benign joint hypermobility syndrome in 10%, myofascial syndrome in 5%, tendonitis in 2% and fibromyalgia in 1%. (Zapata AL. Moraes AJ. Leone C. Doria-Filho U. Silva CA. Pain and musculoskeletal pain syndromes related to computer and video game use in adolescents. European Journal of Pediatrics. 165(6):408-14, 2006 Jun).
Another study in college students showed that of those students who use a laptop computer for all computer use, 90.1% reported musculoskeletal complaints. The majority of female college students in this study reported musculoskeletal discomfort during or after computer use. Although a statistical correlation could not be made, students using laptop computers reported a higher incidence of musculoskeletal symptoms than those using desktop computers. (Hamilton AG. Jacobs K. Orsmond G. The prevalence of computer-related musculoskeletal complaints in female college students. Work. 24(4):387-94, 2005).
Alternating between resting the forearms on the work surface and on the chairs' armrests could solicit different muscles during computer work, and could be considered as a strategy for preventing musculoskeletal disorders.
When holding mobile devices for texting purposes, it is best that the head not be in a constant bent-down position, arms and elbows be held at the side of the body, the wrists not cocked up but kept in a slightly bent down position. The thumb and fingers should not press the keyboard with excessive pressure by keeping them as straight as possible. Long messages are best not to be typed on these hand-held devices. The key to prevent repetitive injuries so it does not become chronic pain. The key to prevention is to rest frequently and often. Try resting for equal durations as time worked.
Doping| Sports
August 23, 2008 10:57 amSaturday, August 23, 2008
World Anti-Doping Agency (WADA) lists many compounds such as beta-agonists, corticosteroids, and narcotics in addition to others. Many substances on the list are detrimental for athletic prowess.
Double-blind trials for amphetamines and other stimulants showed that they can enhance performance in short, explosive activities, such as sprinting. Anabolic steroids have been proved beyond any doubt to increase muscle mass and enhance performance among male athletes in sports that require strength, such as weightlifting and shot-putting; in women, they appear to work for endurance sports as well. History provides more circumstantial evidence: In many sports, the amazing rise in performances came to a halt after the crackdown on anabolic steroids began in earnest in the 1980s, and some records have not been broken since then.
One of the hottest substances of the moment, erythropoietin (EPO), has been tested for performance enhancement in only four double-blind trials, they showed that it increased maximum oxygen uptake and performance, but apparently for short durations only. Data are lacking because rigorous trials are expensive, and there's little incentive to fund them.
The drugs' target population, top athletes, usually can't be recruited into studies because it might ruin their careers. Also, the list of substances and combinations is endless; cyclists once used a cocktail of strychnine, cognac, and cocaine with many side effects.
WADA currently does research to improve detection of human growth hormone, a banned substance that appears to be very popular and is very hard to detect. In healthy people, for instance, an overdose of insulin–another listed substance that few believe does athletes any good–can lead to a fatal drop in blood sugar levels.
WADA wants to protect athletes from any drug they don't need, if only to send a message to their young fans. Practically anything can end up on WADA's list–and that athletes risk ending their careers by taking something that doesn't bring them one bit closer to a gold medal. (ref: Martin Enserink, Science 1 August 2008:Vol. 321. no. 5889, p. 627)
Sprinting | Muscles
August 17, 2008 12:57 amSunday, August 17, 2008
The forces produced by an athlete during the support phase of a sprint run are a vital determinant of the outcome of the performance. The purpose of this study was to improve the understanding of sprint technique in well-trained sprinters through the comprehensive analysis of joint kinetics during the support phase of a maximum-velocity sprint.
It was found that the knee moment did not contribute substantially to power generation during the latter part of the support phase. This may be explained in part by the specific technical requirements of the maximum-velocity phase of the sprint. However, major periods of power generation of the hip extensors in early stance and of the plantar flexors in late stance were observed. The knee extensors played a negligible role in positive work generation throughout stance. The action of the knee joint during the support phase may therefore have been more of a facilitator for the radial transfer of power from the hip through the ankle on to the track. (Bezodis IN. Kerwin DG. Salo AI. Lower-limb mechanics during the support phase of maximum-velocity sprint running. Medicine & Science in Sports & Exercise. 40(4):707-15, 2008 Apr).
Another study showed that (1) the difference in leg stiffness between endurance-trained and power-trained athletes is best attributed to increased joint stiffness, and (2) the difference in joint stiffness between the two groups may be attributed to a lack of similarity in the intrinsic stiffness of the muscle-tendon complex rather than in altered neural activity. (Hobara H. Kimura K. Omuro K. Gomi K. Muraoka T. Iso S. Kanosue K. Determinants of difference in leg stiffness between endurance- and power-trained athletes. Journal of Biomechanics. 41(3):506-14, 2008).
This study showed that the ability to produce force quickly, as measured by the time to achieve 60% of maximum voluntary contraction is related to sprinting performance, with the coefficient of determination accounting for 53% of the variance in the data. These data also show that sprinting ability is linked with drop jump performance, especially the drop jump from a height of 30 cm. It is suggested that the above tests may prove useful in preparing and testing the sprinting ability and sprint specific strength levels. (Bissas AI. Havenetidis K. The use of various strength-power tests as predictors of sprint running performance. Journal of Sports Medicine & Physical Fitness. 48(1):49-54, 2008 Mar.)
In a study to investigate the effects of performing heavy back squats and heavy front squats on the average speed during each 10-m interval of 40-m sprint trials. Heavy back squats produced significantly greater speeds compared with the heavy front squats treatment. It is suggested that coaches could incorporate heavy back squats into the warm-up procedure of athletes to improve sprinting performance. (Yetter M. Moir GL. The acute effects of heavy back and front squats on speed during forty-meter sprint trials. Journal of Strength & Conditioning Research. 22(1):159-65, 2008).
Swimming| Warm-up
August 11, 2008 11:40 pmWatching the Olympics, a ritual and a routine that Michael Phelps performs just prior to swimming competitively will be noted. Not only does he stretch his lower extremity muscles, he also shakes his arm muscles to keep them loose. He has perfected his technique of loosening his shoulder girdle muscles and you can virtually see muscles being individually shaken from the shoulder, down. These muscles include the deltoid, biceps, triceps and forearm muscles. He then flaps his arms away from the body to actively contract these muscles, as well as the trapezius. His final exercise is to actively contract the latissimus dorsi muscles by bringing his shoulder into extension three times behind his body, which at the same time stretches the pectoralis major. The movements are coordinated and purposeful, and with an arm-span of 6 ft and 7", this movement is likened to a Condor about to fly. To the viewers who understand functional anatomy, it is such a treat to see all the important muscles for swimming in motion exercised by this champion set to win five more gold medals, in addition to the three that he has already won.
Gymnastics| Pain
August 10, 2008 9:46 pmSunday, August 10, 2008
As you view the Olympics gymnasts perform, do you wonder about their pain problems and what muscles may be prone to injuries and how to minimize injuries?
Pain is a serious problem in advanced level female artistic gymnasts because it decreases the performance. The pain is due to the high numbers of hours spent in training sessions and may be associated to injuries that have relatively high incidence and severity in these athletes.
This study investigated the role of a preventive-compensative physical activity program, implemented in the warm-up and the cool-down session of standard training, in the prevention and reduction of the pain syndromes by evaluating thirty elite level female athletes, 10-14 years old, who were followed for 12 weeks during the competition preparation period. Fifteen athletes were trained with preventive-compensative motor program implemented in the ordinary training (intervention group) and fifteen (control group) followed the standard training. All athletes completed a self-administered questionnaire regarding the pain intensity with a Visual Analogue Scale pre- and post- intervention. The experimental protocol consisted of three steps: the treatment of the shortened muscle chains according to Active Posture Reeducation method, the proprioceptive-coordinative training with wobble board and the mobilization and stretching of back using fitball.
Before intervention, the pain in practicing this sport was reported by 83% of all the athletes. The most common primary pain sites were the ankle and low back; the pain anatomical location was correlated to the training. After intervention, low back pain assessment showed a decrease of pain identified as mild (from 56% to 44%) or moderate (from 33% to 22%) and a disappearance of severe pain (from 11% to 0%). Ankle pain decreased and/or disappeared: the mild pain from 33% to 27%, moderate from 27% to 13% and severe from 13% to 0%. The pain analysis did not show different results in the control group.
The results indicated that the performed preventive-compensative training is of value, in a short time perspective, in preventing and reducing the pain syndromes in these athletes.( Mirca M. Eleonora S. Edy B. Marina P. Marco M. Pain syndromes in competitive elite level female artistic gymnasts. role of specific preventive-compensative activity. Italian Journal of Anatomy & Embryology. 113(1):47-54, 2008 Jan-Mar.)
Scapular muscle performance in elite, young gymnasts is characterized by increased protraction strength and altered muscular balance around the scapula compared with nonathletic adolescents. (Cools AM. Geerooms E. Van den Berghe DF. Cambier DC. Witvrouw EE. Isokinetic scapular muscle performance in young elite gymnasts. Journal of Athletic Training. 42(4):458-63, 2007 Oct-Dec).
To evaluate a specific segmental muscle training program of the lumbar spine in order to prevent and reduce low back pain in young female teamgym gymnasts. Teamgym is a team sport comprising three events: trampette, tumbling and floor program. In a recent study, it was found that teamgym gymnasts practice and compete despite suffering from back pain. Specific muscle control exercises of the lumbar spine have shown good results in reducing pain intensity and functional disability levels in patients with low back pain.
Fifty-one gymnasts, with and without LBP, 11-16 years old, from three top-level gymnastics team participated in the study comprising 12 weeks. Every day the gymnasts answered a questionnaire regarding low back pain. After baseline (4 weeks) the intervention group performed a specific segmental muscle training program. Twenty-four gymnasts (47%) reported low back pain during baseline. Nine gymnasts failed to answer the questionnaire every day and the following results are based on 42 gymnasts (intervention group, n = 30, and control group, n=12). Gymnasts in the intervention group reported significantly less number of days with low back pain at completion compared to baseline (P=0.02). Gymnasts in the control group showed no difference in terms of days with low back pain or intensity of low back pain between baseline and completion. Eight gymnasts (out of 15) with LBP in the intervention group became pain free.
Specific segmental muscle control exercises of the lumbar spine may be of value in preventing and reducing low back pain in young teamgym gymnasts. (Harringe ML. Nordgren JS. Arvidsson I. Werner S. Low back pain in young female gymnasts and the effect of specific segmental muscle control exercises of the lumbar spine: a prospective controlled intervention study. Knee Surgery, Sports Traumatology, Arthroscopy. 15(10):1264-71, 2007 Oct).
In the floor exercise, a gymnast may receive a general composition score deduction associated with a lack of diverse tumbling sequences. Diversity in tumbling is defined as the ability to tumble both forward and backward, as well as twist and flip. A coach's ability to direct technical and physical training for these skill varieties is enhanced when thorough descriptions of the skills are available.
The aim of this study was to describe and compare muscle activation of the lower extremity in various tumbling sequences characterized by differing body orientations. The stretch-shortening cycle actions during the take-off portion of four different tumbling sequences were analysed and the results compared across muscles and type of take-off (forward vs. backward, twisting vs. non-twisting).
Thirteen female gymnasts performed three trials each of round-off flic-flac to backward layout and to backward layout with longitudinal axis twist, and front flic-flac to forward layout and to forward layout with longitudinal axis twist. Activation onset was assessed as an increase of the EMG of 200% above noise before initial floor contact. The EMG was normalized to peak values for each muscle bilaterally during each take-off.
Results showed that muscle activation characteristics in the pre-activation and impact phase (contact to maximal floor depression) differed between tumbling series. Backward take-offs were characterized by longer contact times, greater relative activity of the gastrocnemius compared with the vastus lateralis during pre-activation, and greater biceps femoris activation during impact compared with forward take-offs. Twisting backward was associated with reduced muscle activity of the twisting limb, while twisting forward was associated with increased muscle activation on the twisting limb. These differential effects related to the specific nature of the take-off indicate that training to enhance the stretch-shortening cycle action in gymnasts must be specific to the orientation requirements of each specific skill. (McNeal JR. Sands WA. Shultz BB. Muscle activation characteristics of tumbling take-offs. Sports Biomechanics. 6(3):375-90, 2007 Sep).
Swimming| Efficiency| Muscles
August 6, 2008 1:50 pmWednesday, August 06, 2008
I decided to add this extra blog today with more information for all the swim enthusiasts since swimming is such a popular Olympic sports.
The purpose of the following study was to analyze the relationships between energy cost, swimming velocity, stroke frequency and stroke length in top-level swimmers. Eighteen elite swimmers (four freestylers, five backstrokers, five breaststrokers and four butterflyers) performed an intermittent set of nx200 m swims (n<or=8) with increasing velocity. The study examined the oxygen consumption, lung ventilation, expiratory gases and blood lactate concentration.
Backstroke, Breaststroke and Butterfly strokes: increases of stroke frequency were associated to increases of energy cost, even when controlling the velocity.
Breaststroke: Increases in stroke length promoted significant decreases in the energy cost.
All competitive swimming techniques: There was a significant and polynomial relationship between velocity and stroke frequency.
Freestyle and Butterfly stroke: The polynomial relationship between velocity and stroke length was significant.
It is concluded that manipulation of stroke mechanics variables (stroke frequency and stroke length) may be one of the factors through which energy cost in competitive swimming can be altered for a given velocity.( Barbosa TM. Fernandes RJ. Keskinen KL. Vilas-Boas JP. The influence of stroke mechanics into energy cost of elite swimmers. [Comparative Study. Journal Article] European Journal of Applied Physiology. 103(2):139-49, 2008 May)
Another study using kinetic (3-D force plate), kinematic (videography) and temporal characteristics of backstroke turns by 20 male and 16 female swimmers were recorded to identify and describe key elements of backstroke turning performance. Data were recorded during a 50 m maximum effort swim in a 25 metre pool.
Four key factors were identified from a principle components factor analysis–anthropometry and force, post-turn velocity, force preparation and rotational skills. Implications from the findings were that age-group backstrokers should 'hit the wall hard' with relatively extended legs to reduce swim distance and push-off deceleration; use minimal wall contact time, and maximise forces to develop high horizontal velocities in a streamlined position. (Blanksby B. Skender S. Elliott B. McElroy K. Landers G. An analysis of the rollover backstroke turn by age-group swimmers Sports Biomechanics. 3(1):1-14, 2004)
Competitive swimming consists of four strokes and utilizes both upper and lower extremities in moving forward through the water. Shoulder and arm mechanics are similar in the freestyle, butterfly, and backstroke. Much of the forward propulsion created during the pull-through phase of these strokes is the result of lift forces produced by the traversing motion of the hand and forearm.
Shoulder adduction and internal rotation (primarily performed by pectoralis major and latissimus dorsi) are important in stabilizing the shoulder and allowing the body to be moved forward over the hand during swimming.
The same is true of the rapid motion portion of the breaststroke pull-through. Similarly, the flutter, or dolphin, kicks used in freestyle, backstroke, and butterfly produce forward motion by creating forward lift, and the lower leg "paddles" against the water. Knee motion is from approximately 0 to 90 degrees. In breaststroke, water is "whipped" out from between the rapidly closing legs; flexion is up to 140 degrees. All these forces are meant to overcome drag, which is the force resisting forward motion.( Richardson AR. The biomechanics of swimming: the shoulder and knee. Clinics in Sports Medicine. 5(1):103-13, 1986)
Swimming| Injuries
August 2, 2008 11:39 pmSunday, August 03, 2008
With the event of the upcoming 2008 Olympics in Beijing , the eToims blog news will relate to the muscles and nerves responsible for performing the various sports events in the Games. This week we hail the Olympics with blogging about injuries associated with competitive swimming.
The shoulder in swimming is subjected to multiple factors that can lead to a high injury rate. To prevent injury, one must understand the biomechanics of swimming. This paper describes the electromyographic and cinematographic findings of 12 shoulder muscles in competitive swimmers without shoulder pain. The results show the three heads of the deltoid and the supraspinatus functioning in synchrony to place the arm at hand entry and exit, the rhomboids and upper trapezius to position the scapula for the arm, the pectoralis major and latissimus dorsi to propel the body, the subscapularis and serratus anterior as muscles with constant muscle activity, the teres minor functioning with the pectoralis major, and the infraspinatus active only to externally rotate the arm at midrecovery. This information is important to design optimal preventative and rehabilitative exercise programs. (Pink M. Perry J. Browne A. Scovazzo ML. Kerrigan J. The normal shoulder during freestyle swimming. An electromyographic and cinematographic analysis of twelve muscles. American Journal of Sports Medicine. 19(6):569-76, 1991 Nov-Dec.)
The findings of this next study indicate that a relationship does exist between shoulder injury and the temporal recruitment patterns of the scapular rotators (trapezius and serratus anterior), such that injury reduces the consistency of muscle recruitment. They further suggest that injured subjects have muscle function deficits on their unaffected side also. (Wadsworth DJ. Bullock-Saxton JE. Recruitment patterns of the scapular rotator muscles in freestyle swimmers with subacromial impingement. International Journal of Sports Medicine. 18(8):618-24, 1997).
Swimmers with unilateral shoulder pain related to swimming compared to a control group with no present or previous history of shoulder pain showed that both groups of swimmers exhibited increased external range of motion and reduced internal range of motion compared with normalized data, but no between-group or side-to-side differences were detected. These findings suggest that prevention or rehabilitation of swimmer's shoulder might not solely involve strengthening of the external rotators of the shoulder joint. Attention might also be drawn toward correction of a possible deficit in internal rotational strength. Changes in shoulder range of motion seem unrelated to the occurrence of shoulder pain. (Bak K. Magnusson SP. Shoulder strength and range of motion in symptomatic and pain-free elite swimmers. (American Journal of Sports Medicine. 25(4):454-9, 1997)
Breaststroke swimmers are at significant risk of groin injury, groin injury is positively correlated with increased magnitude of breaststroke training, and groin injury may prevent participation in practices and competitions.
The purpose of this following study was to examine the influence of a 3-wk period of electrostimulation training on the strength of the latissimus dorsi muscle and the swimming performances of 14 competitive swimmers divided into 7 electrostimulated (EG) and 7 control swimmers (CG). The peak torques registered during the flexion-extension of the arm was determined with the help of an isokinetic dynamometer at different velocities (from -60 degrees.s(-1) to 360 degrees.s(-1)). Performances were measured over a 25-m pull buoy and a 50-m freestyle swim. For Electrostimulated Group, a significant increase of the peak torques was measured in isometric, eccentric, and concentric conditions. The swimming times declined significantly by 0.19 +/- 0.14 s, for the 25-m pull-buoy, and by 0.38 +/- 0.24 s, for the 50-m freestyle. For the Control Group, no significant difference was found for any of the tests. These results showed that an electrostimulation program of the latissimus dorsi increased the strength and swimming performances of a group of competitive swimmers. (Pichon F. Chatard JC. Martin A. Cometti G. Electrical stimulation and swimming performance. Medicine & Science in Sports & Exercise. 27(12):1671-6, 1995)
Surfing| Injuries
July 26, 2008 12:33 amSaturday, July 26, 2008
Surfing has experienced a 'boom' in participants and media attention over the last decade at both the recreational and the competitive level. However, despite its increasing global audience, little is known about physiological and other factors related to surfing performance. Time-motion analyses have demonstrated that surfing is an intermittent sport, with arm paddling and remaining stationary representing approximately 50% and 40% of the total time, respectively. Wave riding only accounts for 4-5% of the total time when surfing. It has been suggested that these percentages are influenced mainly by environmental factors.
Competitive surfers display specific size attributes. Such surfers tend to have a husky, muscular body build and lower height and body mass compared with other matched-level aquatic athletes. Surfers possess a high level of aerobic fitness. Upper-body ergometry reveals that peak oxygen uptake (VO2peak) values obtained in surfers are consistently higher than values reported for untrained subjects and comparable with those reported for other upper-body endurance-based athletes. Heart rate (HR) measurements during surfing practice have shown an average intensity between 75% and 85% of the mean HR values measured during a laboratory incremental arm paddling VO2peak test. Moreover, HR values, together with time-motion analysis, suggest that bouts of high-intensity exercise demanding both aerobic and anaerobic metabolism are intercalated with periods of moderate- and low-intensity activity soliciting aerobic metabolism.
Minor injuries such as lacerations are the most common injuries in surfing. Overuse injuries in the shoulder, lower back and neck area are becoming more common and have been suggested to be associated with the repetitive arm stroke action during board paddling. Further research is needed in all areas of surfing performance in order to gain an understanding of the sport and eventually to bring surfing to the next level of performance. Mendez-Villanueva A. Bishop D. Physiological aspects of surfboard riding performance. Sports Medicine. 35(1):55-70, 2005.
A prospective study of acute competitive surfing injuries was carried out at 32 professional and amateur surfing contests worldwide between 1999 and 2005. All acute injuries sustained during competition were recorded by on-site medical personnel. The wave size, type of seafloor, and number of surfing heats were also recorded for each day. The total number of injuries was divided by the total number of athlete exposures to determine injury rates. Risk of injury was 2.4 (95% confidence interval, 1.5-3.9) times greater when surfing in waves overhead or bigger relative to smaller waves and 2.6 (95% confidence interval, 1.3-5.2) times greater when surfing over a rock or reef bottom relative to a sandy bottom. There were 13 acute surfing injuries per 1000 hours of competitive surfing. The risk of injury was more than doubled when surfing in large waves or over a hard seafloor.( Nathanson A. Bird S. Dao L. Tam-Sing K. Competitive surfing injuries: a prospective study of surfing-related injuries among contest surfers. American Journal of Sports Medicine. 35(1):113-7, 2007).
Surfers considered the risk of head injury while surfing as moderate or high, and only 12 (1.9%, 95% CI 1.0-3.3) reported routine use of headgear. The surfers were more likely to believe that there was a higher risk of head injury in other sports and physical activities (P < .001). Although 475 surfers (73.8%, 95% CI 70.2-77.1) thought that surfers who wear headgear are less likely to become injured, 400 (62.1%, 95% CI 58.2-65.9) reported that headgear restricted surfing performance and that they would rather surf without it. The main reasons for not wearing headgear were "no need," discomfort, claustrophobia, and effects upon the senses and balance. Although most surfers acknowledge some risk of head injury, headgear is rarely used and barriers to its use are apparent. Research is required to clarify the risk of head injury among surfers and the effectiveness of headgear in reducing injury risk. Until this evidence is available, educational initiatives, improved headgear design, and profile within the surfing culture would be required to increase rates of wearing headgear. (Taylor DM. Bennett D. Carter M. Garewal D. Finch C. Perceptions of surfboard riders regarding the need for protective headgear. Wilderness & Environmental Medicine. 16(2):75-80, 2005.
Golf| Injuries |Back pain
July 18, 2008 12:13 amFriday, July 18, 2008
A recent article in the Wall Street Journal (WSJ.com - Health Matters ) on June 14, 2008 on golf injuries initiated this blog.
Nearly 16% of Australian amateur golfers may expect to sustain a golf-related injury per year. The injuries in golf are most likely sustained in the lower back region as a result of the golf swing. The lower back was the most common injury site (18.3%), closely followed by the elbow/forearm (17.2%), foot/ankle (12.9%), and shoulder/upper arm (11.8%). A total of 46.2% of all injuries were reportedly sustained during the golf swing, and injury was most likely to occur at the point of ball impact (23.7%), followed by the follow-through (21.5%). Based on statistical analysis, only the amount of game play and the last time clubs were changed were significantly associated with the risk of golf injury. Other factors such as age, gender, handicap, practice habits, and warm-up habits were not significant. (McHardy A. Pollard H. Luo K. One-year follow-up study on golf injuries in Australian amateur golfers. American Journal of Sports Medicine. 35(8):1354-60, 2007).
In another study of 12 golfers, the myoelectric activity of the lumbar erector spinae (low back spinal muscles) and the external obliques (abdominal wall muscles) was recorded via surface electromyography, while the golfers performed 20 drives. The results showed that the low-handicap low back pain (LBP ) golfers tended to demonstrate reduced erector spinae activity at the top of the backswing and at impact and greater external obliques activity throughout the swing. The high-handicap LBP golfers demonstrated considerably more erector spinae activity compared with their asymptomatic counterparts, while external obliques activity tended to be similar between the groups. The reduced erector spinae activity demonstrated by the low-handicap LBP group may be associated with a reduced capacity to protect the spine and its surrounding structures at the top of the backswing and at impact, where the torsional loads are high. When considering this with the increased external obliques activity demonstrated by these golfers, it is reasonable to suggest that these golfers may be demonstrating characteristics/mechanisms that are responsible for or are a cause of LBP. (Cole MH. Grimshaw PN. Electromyography of the trunk and abdominal muscles in golfers with and without low back pain. Journal of Science & Medicine in Sport. 11(2):174-81, 2008 )
Performance was affected in 78.9% of cases, with 69.7% of the injured golfers missing games or practice sessions due to injury. Golfing injuries appear common and have a substantial impact upon the injured golfer. As lower back strains are the most common injury, strategies such as performing an appropriate warm-up could be investigated to determine the possible injury prevention benefits for golfers.
Many of these individuals have pre-existent back problems and have frequented chiropractors. Re-injury to previously injured nerve roots and muscles predispose these individuals to chronic pain.
