Acute response to submaximal and maximal exercise consequent to beta-adrenergic blockade: implications for the prescription of exercise.

Forty-seven healthy male subjects, 17 to 34 years old, completed a test to exhaustion on a motor-driven treadmill to determine their maximal oxygen uptake. A second test was administered 2 days later during which the subject walked for 20 to 25 minutes at a steady-state level representing 60% of the maximal oxygen uptake as determined in the first test. The grade was then increased every 2 minutes until the subject reached the state of exhaustion. After the second test, the subjects were randomly assigned, in a double-blind manner, to either placebo, propranolol (160 mg/day), or atenolol (100 mg/day) treatment for 7 days. Exactly 1 week from the time of the second test, and 3 hours after the last medication, the subjects completed the final exercise test using the same treadmill protocol administered in the second test. Heart rate and systolic blood pressure at rest and during submaximal steady-state exercise were significantly reduced by both drugs, whereas diastolic pressure was unaffected. During submaximal steady-state exercise, cardiac output was reduced in both the placebo and atenolol groups, stroke volume was increased in both atenolol and propranolol groups, oxygen uptake was reduced in the atenolol group, pulmonary ventilation was reduced in both propranolol and atenolol groups, and the respiratory exchange ratio remained unchanged. With maximal exercise, treadmill time was significantly reduced with propranolol, pulmonary ventilation and heart rate were reduced significantly with both drugs, but maximal oxygen uptake remained unchanged. Thus, beta blockade does not appear to limit ability to exercise. However, there appears to be a significant advantage to using a cardioselective rather than a nonselective beta-blocking agent.

Patellalgia.

In brief: Knee pain relating to or arising from the patellofemoral articulation is common in athletes. While direct trauma can cause this pain, patellofemoral malalignment and/or tracking problems seem to be its major source. This paper reviews the functional anatomy of the patella and describes the diagnostic and treatment procedures recommended for investigating and treating this condition. Most patients improve after an initial course of conservative treatment. Proximal or distal realignment may be surgically performed in patients who don't respond to conservative treatment. Patellectomy leaves some weakness in the quadriceps and should be used only as a last resort.

Patellofemoral syndrome: therapeutic regimen based on biomechanics.

The clinician needs to rehabilitate the patient with the patellofemoral syndrome based on biomechanics and anatomy. If we understand the function of the patella and the forces acting upon it, we can educate our patients to ensure their compliance through both the treatment phase and future maintenance.

Sports medicine electives. Are they available in Canadian family medicine programs?

Sports medicine is becoming a larger part of a family physicians' practice. We surveyed all family medicine teaching programs in Canada to determine how many offer sports medicine experiences and who teaches them. The study found that few residents have clinical training in sports medicine, though most have attended seminars. Primary care physicians, orthopedic surgeons, physiotherapists, and rheumatologists teach sports medicine.

The effect of bicycling helmets in preventing significant bicycle-related injuries in children.

OBJECTIVE: To identify bicycle-related injuries in children and the effect of helmet use on injury patterns and prevention. DESIGN: A prospective cohort of injured children with case-control design looking at serious head injuries and helmet use. SETTING: A tertiary care childrens' hospital emergency room. PATIENTS: All patients presenting between April 1, 1991 and September 30, 1993, between the ages of 3 and 16 years, with bicycle-related injuries were included. INTERVENTION: The Childrens' Hospital Injury Research and Prevention Program (CHIRPP) Database was used. Standardized information collected on each child included age and sex of the child; nature, location, and time of accident/injury; whether any safety devices were being used at the time of the accident; and the attending physician's determination of the injury(s) and treatment rendered. MAIN OUTCOME MEASURES: Injuries were categorized as major or minor, based upon a consensus of the authors, in a retrospective fashion. RESULTS: Separate bicycle accidents (n = 699) were recorded resulting in 856 injuries. Only 13.7% of the children were wearing helmets at the time of their accidents. Seventy-six serious head injuries were recorded. The risk of serious head injury was significantly greater when a helmet was not worn (chi 2 0.01 < p < 0.05) This represents an odds ratio of 3.12 [confidence interval (CI) = 95% 1.13-8.75]. There was no significant difference in terms of serious injuries overall comparing helmeted and nonhelmeted children (odds ratio = 1.11, 95% CI = 0.72-1.72). CONCLUSIONS: Helmets afford a protective effect with respect to serious head injuries.

Sports Medicine: What family physicians see and what they need to learn.

The relative frequency with which family physicians managed several sports-related problems was studied, as well as their level of comfort with each of the conditions and the sources of information they planned to use to improve their knowledge or skills. Physicians reported greater comfort with conditions they managed more often. Most intended to seek information.

Using an objective structured clinical examination to evaluate competency in sport medicine.

This article discusses the development, format, administration and scoring of the objective structured clinical examination (OSCE) to evaluate competency in sport medicine. The credentials committee of the Canadian Academy of Sport Medicine has developed an examination to evaluate the competency of practicing physicians in the field of sport medicine. The examination is based on a sport medicine matrix that includes five areas: (a) clinical patient care, (b) team and event coverage, (c) medical/legal issues, (d) teaching and administration, and (e) research. The emphasis is on clinical patient care followed by team and event coverage, with the other three areas having a lesser degree of importance. The OSCE format consists of a number of stations or scenarios based on this matrix. The candidates are evaluated on a check list that reflects the emphasis of each station. A typical clinical patient care problem includes check list items related to the history, physical examination, investigations, diagnosis, and treatment. The candidates are also evaluated for their attitudes and techniques on each station. The examination includes volunteer examiners and patients both simulated and real. The candidates are evaluated through the use of checklists that are filled in by the examiners on optical scoring sheets. These are collated and analyzed to generate comparisons between candidates and to determine the psychometric properties of the overall examination. The examination has consistently scored reliability coefficients of 0.8 or greater. The 1993 examination demonstrated reliability coefficients of 0.89-0.97. Interrater reliability was also calculated, and these values ranged from 0.85 to 0.99. The examination also reflects both face and content validity.(ABSTRACT TRUNCATED AT 250 WORDS)