Week 9: physical performance tests in sport Flashcards
What are Physical Performance Tests (PPTs)?
Physical performance tests (PPTs) were developed as measures of function in sport
- A combination of PPTs can be used as part of pre-season screening
- A PPT is a low technology measure that can be performed by everyone from coaches to healthcare professionals to examine components of sport (strength, power, agility
Advantages of Physical Performance Tests (PPTs)
- Easy to administer
- Are not time consuming
- Do not require a great deal of expertise
- Can be completed in multiple settings and locations
Can PPTs be used to predict injury in sport?
systematic review found:
- There is limited evidence to support the use of PPTs to predict injury
- Only 3/23 PPT have some ability to predict injury
- Star excursion balance test
- Closed kinetic chain upper extremity stability test (CKCUEST)
- Seated shot put (2 hands)
Functional movement screen
Functional movement screen: An evaluation tool that attempts to assess the fundamental movement patterns of an individual. It is comprised of seven fundamental movement patterns that require a balance of mobility and stability
- Squat
- Hurdle step
- In- line lunge
- Shoulder mobility
- Active straight leg raise
- Trunk stability push up
- Rotary stability
Scoring
The scores range from zero to three, three being the best possible score
Zero: pain anywhere with movement
1: unable to complete movement
2: movement complete with compensations
3: movement complete
Can the functional movement screen be used to predict injury? Is there an association between FMS scores and injury risk?
There is no relationship between total FMS score and risk of non-contact injuries in athletes
There is no relationship between asymmetry in FMS tests and risk of non-contact injuries
Limitations of physical performance tests
- The measures used in tests are commonly based on reference norms, not sport-specific measures. Applying normal values to a specific population (athletes). example: Pitchers will have greater external rotation on their pitching arm than their non-pitching arm. This external rotation is also greater than the normal population.
- PPTs are unidimensional; they only consider one factor. Example: an athlete can have great biomechanics and terrible fitness
- Not using prospective data to create the tool. Harder and more resource intensive to do than cross sectional studies
- cross sectional studies can’t tell us as much as a prospective study can. tests can’t have predictive values.
Risk factors
Risk factors: type of correlate. It is associated with an increased probability of an outcome, usually an unpleasant one
Characteristics
1. It occurs before the outcome
2. It can be used to divide a population into high risk and low risk subgroups
Differentiate between cross sectional studies and cohort studies.
Cross sectional
- RETROSPECTIVE
- Snapshot of a given point in time
- Primarily used to determine prevalence
- Can determine a correlation but not causation
Cohort studies
- PROSPECTIVE - usually
- Describe the incidence or natural history of a condition
- Measures temporality, therefore can infer causation
- Analyse predictors (risk factors)
- Does not take into account confounding variables
Relative risk
incidence of disease among exposed individuals / incidence of disease among unexposed individuals
- RR of 1.0 indicates no association between exposure and disease
- RR > 1.0 indicates that the exposure increases the incidence of disease
- RR < 1.0 indicates that the exposure provides protection from the disease
Odds ratio
odds of exposure among individuals with disease / odds of exposure among individuals without disease
- OR of 1.0 indicates odds of exposure are similar among those with and without disease
- OR > 1.0 indicates increase likelihood of exposure among diseased subjects
- OR < 1.0 indicates a decreased likelihood of exposure among diseased subjects
Intrinsic and Extrinsic Factors of Sport-Related Injury
Intrinsic risk factors
- Modifiable: fitness, biomechanics, energy availability, psychology
- Non-modifiable: age, sex, anatomy, previous injury
Extrinsic risk factors
- Sport equipment
Is baseline fitness associated with an increased risk of sport-related injury?
A lower VO2max is associated with a higher rate of sport-related injury. Higher VO2 max has a protective effect
Is biomechanical dysfunction associated with an increased risk of sport-related injury?
Scapular dyskinesia is associated with an increased risk of sport-related injury
- risk ratio is above 1
Is there an association with sport equipment and injury risk?
Orthotic use increases the risk of developing medial tibial stress syndrome (shin splints) in runners
- risk ratio above 1
- however this study only inferred causation.
- But we shouldn’t tell people to throw their orthotics out just for this reason. Person might be wearing orthotics to support weakness
- If they have no other risk factors and no good reason to wear orthotics we can tell them to get rid of it
- Orthotics limit the collapse of the arch leading to less pronation
- Arch attenuates the shock from the ground before it propagates upwards
Workload
Workload: quantify work done during a training period. Made up of internal and external load
Internal load: psychophysiological response to external load
- Heart rate
- Heart rate variability
- Rating of perceived exertion
- VO2max
- Blood-Lactate values
External load
- GPS (distance, change in direction, velocity)
- Power (watts)
- Duration (time)
- # jumps, jump height
- # of kicks
Calculating total workload
Combination of internal and external work
- sRPE x duration
- HR x distance
Total external work
- (Power or velocity ) x (duration or distance)
Chronic workload vs acute workload
Chronic workload: over a larger time like a month or quarter
Acute workload: over a week
Ratio of chronic to acute workload important
Are workloads associated with an increased risk of sport-related injury?
- High chronic training loads are a protective factor! - dependson the sport
-High chronic workload combined with a moderate workload ratio (1.02–1.18) had a smaller risk of injury than low chronic workload combined with several workload ratios
What are the characteristics of a good
outcome measure?
Strong Purpose
1. Discriminate among patients/athletes at a point in time
2. Predict a subsequent event or outcome
3. Assess change over time
Psychometric properties
- Validity
- Reliability
- Minimal detectable change (MDC)
- Minimal clinically important difference (MCID)
How can we validate a sport injury prediction tool?
- A strong relationship must be demonstrated between screening test and injury risk.
- The test properties of the marker must be validated in relevant populations.
- If we develop an intervention program in response, an intervention program given to targeted athletes should be more beneficial than the same intervention given to all athletes.
How to create your own injury risk screening
- Conduct a systematic search on the sport of interest
- Find all prospective cohort studies that include risk factors on injury incidence (not prevalence)
- Consider all internal and external risk factors
- Create an assessment tool that incorporates the modifiable risk factors
Implementing an Injury Risk Screening
- Identify athletes who are at risk via screening, assessment, questionnaires. Compare to a normative database for the sport and position if available.
- Address the identified risk factors with prehabilitation - should change the identified risk factors
prevalance vs incidence
Incidence: rate of new events that occur over a particular period of time - example # of acl injuries over a soccer season
Prevalence: # of injuries at a given point of time within a given population - example: halfway through a season how many players have an ACL injury. This can capture players that are still recovering from an ACL.
What was the results of the study
To assess the effect of pre-season fitness on injury rate during the competitive season among professional soccer players
applied preseason fitness to everyone!
An increase in VO2max during pre-season training is associated with a lower injury-risk
