60-Second Summary is a regular feature of OLYMPIC COACH. The brief summaries of recent research or other articles can be read in approximately 60 seconds. To obtain a copy of the articles summarized here, contact your local library. If they do not own the publication, they may obtain a copy of the article for you through interlibrary loan.

• SPORT EFFECT ON BONE DENSITY
• HIP AND GROIN INJURIES
• COACHES AS MANAGERS

SPORT EFFECT ON BONE DENSITY

“Effects of Different Sports on Bone Density and Muscle Mass in Highly Trained Athletes” by Angela Andreoli, Maurizio Monteleone, Marta Van Loan, Luigi Promenzio, Umberto Tarantino and Antonio De Lorenzo. Medicine & Science in Sports & Exercise , April 2001, Volume 33, No. 4, pp 507-511.

Past studies have shown that athletes, especially those who are strength-trained, have greater bone mineral densities than non-athletes; also, strength, muscle mass and maximal oxygen uptake correlate with bone density. Past studies also indicate that strength training and high-impact endurance training increase bone density.

Though the factors associated with attaining optimal bone mineral density (BMD) and bone mineral content (BMC) have not been clearly identified, four factors that play major roles are genetics, exercise, hormonal status and nutrition. It is likely that genetics has the greatest impact, but the other three factors can modify the actual peak bone mass acquired or maintained.

The most effective exercise protocol for establishing and maintaining the highest BMD has not been firmly established, but there is some indication that weightbearing exercise may be more beneficial for bone health than non-weightbearing exercise. Weightbearing activities such as walking have a greater effect than non-weightbearing activities such as cycling and swimming. A reduction in mechanical loading such as bed rest or space flight leads to bone loss.

The purpose of the authors’ study was to investigate the effects of different high-intensity activities on BMD and appendicular muscle mass (AMM) in male athletes who train in different activities and have differing amounts of mechanical loading on the skeleton. Sixty-two Caucasian male subjects ranging in age from 18 to 25 years participated in the study. The sample included three groups of athletes (12 judo, 14 karate and 24 water polo) and 12 non-athletes who served as a control group. None were taking medications or drugs that affect bone and muscle metabolism.

The results of the study show that the athletes had significantly greater BMD and AMM than the non-athletes. The finding was similar to those reported by other researchers, and it has been accepted that weightbearing forms of vigorous exercise are associated with greater levels of BMD. The judo athletes, practicing a high-intensity weightbearing sport, had higher values compared with other athletes.

Bone density increases at sites of maximum stress, though the physiological mechanisms involved in the response of bone cells to mechanical stress are still unclear. Physical activity leads to greater bone density in children and adolescents, and to a minor extent in adults. A variety of other factors such as dietary intake, previous physical activity as a child, hormones and genetics may be responsible for differences observed in the present study. More research is needed to understand the interrelationship among those factors.

In conclusion:

	1.	physical activity appears to have a beneficial effect on bone mass
	2.	physical activity with greater mechanical loading appears to result in greater bone mass than with non-weightbearing activities, and
	3.	there appears to be a site-specific skeletal response to the type of loading at each BMD site.

HIP AND GROIN INJURIES

“Hip and Groin Injuries in Athletes” by Kyle Anderson MD, Sabrina M. Stickland MD and Russell Warren MD. The American Journal of Sports Medicine, Vol. 29, No. 4, pp 521-533.

Athletic injuries to the hip and groin occur less commonly than injuries to other extremities, but they can result in lengthy rehabilitation. Therefore, an accurate diagnosis and a well-organized treatment plan are of great importance. Many hip and groin injuries may require several different medical and surgical specialists making a multidisciplinary approach to treatment.

Anatomic and biomechanical considerations for injuries in the hip and groin areas are among the most complex in the musculoskeletal system making their management challenging. Loads of up to eight times the body weight have been demonstrated in the hip joint during jogging with potentially greater loads present during vigorous athletic competition. The hip structure is uniquely adapted to the transfer of such forces. The body’s center of gravity is located within the pelvis, anterior to the second sacral vertebra so loads that are generated or transferred through this area are important in almost every athletic endeavor.

Some common hip and groin conditions affecting athletes are:

Muscle strains are among the most common injuries of the hip and groin resulting from athletic competition. They usually occur in muscles that cross two joints during an eccentric contraction (when external load exceeds muscle force). Strengthening these muscles with appropriate stretching and warm-ups aids in injury prevention. Groin or medial thigh pain is the most common complaint. Initial treatment of muscle strains involves control of hemorrhage and edema with a compressive wrap, ice and rest. After pain is gone, gentle range of motion exercises may be started. Non-steroidial, anti-inflammatory medications may be used if appropriate. After short-term recovery is complete, strengthening should become the focus so the long-term muscle function is not affected.

Hip and thigh contusions may occur as the result of a direct blow to the iliac crest (the upper border of the ilium, a pelvic bone) or as the result of a fall. Initial treatment usually focuses on minimizing swelling and bleeding with compression and ice. Hip should be rested in a position of comfort, and patient should walk with crutches. Do gradual stretching and strengthening of adjacent muscles before resuming activity. Padding modification may allow earlier participation in contact sports. Some physicians may consider the use of a local anesthetic injection to allow continued participation in sports.

Avulsion and apophyseal injuries (tearing off of a bone fragment) about the pelvis are more common in young patients with an immature skeleton. They occur at almost every major muscle attachment and are caused by a violent muscle contraction, usually eccentric. Initial treatment usually includes comfortable positioning with protected weightbearing crutches until the patient is pain-free. After pain subsides, light stretching and weightbearing can be started. After full, pain-free range of motion is achieved, strengthening can begin. Athletes should not return to competition until full strength and motion are restored. Surgical fixation may be considered if the fragment is of sufficient size to contain hardware and the displacement is two centimeters or greater.

Hip dislocation and subluxation (partial dislocation) tend to occur secondary to a collision in skiing and contact sports. Although complete hip dislocation is uncommon in athletics, partial dislocation may be more frequent but is poorly recognized. Dislocation with fracture requires surgery. Treatment for dislocations without fractures may be crutches and partial weightbearing for six to eight weeks with gradual range of motion and strengthening afterward. Loose bone fragments, which are the result of a dislocation or subluxation, may be removed by hip arthroscopy.

Labral tears, historically associated only with major trauma such as posterior hip dislocations, are shown to be related to subluxations and excessive stress on the labrum (fibrous ring of cartilage attached to the rim of a joint). Appropriate treatment should begin with partial weightbearing for four weeks. A local anesthetic injection may be both diagnostic and therapeutic. For athletes not responding to non-operative treatment, surgery (typically arthroscopic) may be an option.

Hip fractures of the proximal femur are unusual in athletes. These fractures are reported to occur from participation in cross-country and alpine skiing, and have been termed, “skier’s hip.” These fractures are considered a surgical emergency.

Groin pain and hernias account for only a small percentage of athletes’ visits to clinics but are responsible for a large portion of time lost from competition. The “ sports hernia” has become a common injury in athletes who do a repetitive amount of twisting and turning at speed such as ice hockey, soccer, tennis and field hockey players. The frequency of this diagnosis may be due to the increased awareness of trainers and physicians. Also, off-season conditioning may concentrate on strengthening the lower extremities but neglect the abdominal musculature, causing a pelvic imbalance. Non-operative treatment is occasionally effective for groin injuries, and surgery can be considered if non-operative treatment fails.

This lengthy article also discusses other types of hip and groin injuries such as snapping hip syndrome, stress fractures and osteoarthritis. The information given in this 60-Second Summary is only a small portion of the information on hip and groin injuries provided by the authors.

In conclusion, “Injuries to structures about the hip joint occur despite the fact that these structures are well-adapted to withstand forces of up to several times body weight. Information is slowly increasing regarding intraarticular hip abnormalities as well as the many complex soft tissue injuries about the pelvis. This increasing body of knowledge spans the expertise of several medical specialties and reinforces the need for a multidisciplinary approach to these athletic injuries. The osseous (relating to bone) and soft tissue conditions briefly summarized in this article represent those most commonly considered in the differential diagnosis of hip pain in athletes.”

COACHES AS MANAGERS
“The Coach-Management Relationship,” Gene Schembri, The Sport Educator, Australia, Vol. 13, No. 1, 2001, pp 8-11.

Training in management enhances coaches’ ability to balance on and off-field roles. Actually, coaching and management skills compliment each other. Individuals that are good in their sport also need to have the basis for handling budgets, planning and designing programs, etc. This allows them to ensure their sport is getting a fair portion of resources and using them efficiently.

Effective coaches may not be managers, but they have well-developed management and people skills that allows them to get on with doing a better job of coaching. Strategies initiated by the coach and by management will help both parties reach a better understanding. Some suggested strategies are briefly discussed.

Coach-initiated strategies:

	1.	Develop self-management skills such as time management, prioritizing, computer, information management and personal health and welfare skills.
	2.	Improve skills that deal with others, for example, communication, negotiating, team-building, the ability to manage upward, media and delegating skills.
	3.	Learn to manage others. This range of skills includes motivation, providing performance feedback, appraising/evaluating staff, setting goals, planning and budget management.

Management-initiated strategies:

	1.	Employment contracts--important to management and coaches to have a signed contract with a current job description.
	2.	Job descriptions should be reviewed, particularly if an organization makes a significant strategic shift.
	3.	Codes of conduct are useful in protecting coaches, ath letes and organizations.
	4.	Performance measures for coaches are important for coaches as well as athletes. They should be conducted at least once a year doing a fair assessment of coach performance and providing feedback for further professional development.
	5.	Ongoing communication is best done through a schedule of regular formal and informal meetings. It is usually more effective in meetings that have a prepared agenda. It is important to communicate directly with the individual(s) that need the information.
	6.	Develop a calendar that includes all external events such as competitions and sponsor meetings. Include coach-management strategies and build in some fun!
	7.	Strategic planning that aligns coach and management actions in a team effort to promote improved athletic performance.
	8.	Openness is the core of enduring relationships. On a day-to-day basis, deal with honesty and openness.
	9.	Realistic expectations should be used in assessing coach performance.

The coach-manager relationship is one of coaches’ key off-field roles, and it needs to be well developed for an effective athlete support system. The relationship is enhanced when coaches’ personal and leadership/management skills are also strong.