Movement Screening and Physical Capacity Assessments

Louis P Howe and Paul . Read

Highlights

• • Movement screening and physical capacity assessments provide coaches with information that supports the decision-making processes when designing training programmes, by identifying an athlete’s strengths and weaknesses.
• • Movement screening should be implemented using methods that identify an athlete’s level of competence to perform the movement patterns they will be using during strength training.
• • When movement faults exist during a screen, an investigator)' process should be implemented to identify the cause, which will enable coaches to select corrective strategies that will be successful.
• • Physical capacity assessments provide coaches with data to examine athletic performance qualities.
• • Strength diagnostic testing assesses an athlete’s ability to produce force under varying conditions, while tissue capacity assessments provides data on the ability of the musculo- tendon unit to tolerate load.

Introduction

A comprehensive assessment of general athletic qualities is a fundamental component in the design of an effective strength and conditioning (S&C) programme. While performance- related tests (e.g. K0_2max testing) are associated directly with distance running, movement screening and physical capacity assessments provide valuable information that will also guide training decisions. Although not considered ‘sport-specific’ in this context, they are ‘sportrelevant’. Specifically, movement screening provides coaches with an indication of an athlete’s readiness to perform strengthening exercises, while physical capacity assessments support coaches in identifying functional deficits that may (positively or negatively) impact running performance. The aim of this chapter is to provide coaches with the tools to design an effective testing battery that will generate useful data and form the basis of a successful S&C programme. Additionally, a range of considerations will be discussed to ensure reliable data are collected through the standardisation of testing procedures. Where available, normative data will be provided to support the coach’s interpretation of assessment results.

Purpose of Screening and Assessment

Establishing baseline measures for movement skill and physical capacities should be the starting point in the training of relevant general qualities (i.e. strength) that may result in improved running performance and reduced injur)' risk. The data produced from these tests can inform the training process through the following mechanisms:

• 1. Identification of functional deficits that may limit performance and increase injury risk. This ensures prioritisation of training for underdeveloped physical qualities, allowing coaches to individualise programme design. For example, decreased strength of the plantar flexor musculature is related to increased risk for developing Achilles tendinopathy (O’Neill et al., 2016). This can be identified during testing of tissue capacity with the calf raise test.
• 2. Investigate movement quality during fundamental patterns that are relevant to running. For example, poor control of the lumbopelvic region and lower extremity in the frontal and transverse plane during single-leg movements (e.g. single-leg squat) is predictive of displaying the same mechanics during the stance phase of running (Whatman et al., 2011).
• 3. Determine an athlete’s preparedness for loading. This should be the primary objective for screening movement quality. Although competency in bilateral squatting shares few mechanical similarities to running, it does provide insight into whether an athlete possesses acceptable technique prior to loading this movement to improve maximal strength.
• 4. Establish baseline measures to determine whether a training programme successfully achieves its desired goal. This can be a strong motivational tool for coaches to employ as it allows them to demonstrate to their athletes the “fruit of their labour”. As a result, buy-in towards future programmes will be enhanced.
• 5. Baseline measures recorded during the assessment process can also inform future rehabilitation programmes. Following injury, functional deficits will be present that result in aberrant movement skill (Decker et al., 2002), decreased range of motion (Askling et al., 2006) and diminished levels of strength (Mucha et al., 2017). In addition, coaches may choose to include routine testing as part of pre-injury screening to individualise their return-to-sport criteria.

Accuracy in Testing

Prior to the design of a testing battery, coaches must consider the validity and reliability of each test to determine the accuracy of the results. This information will support the coach’s interpretation, allowing for functional deficits to be identified and subsequently targeted during training. Validity, defined in simple terms as the test’s ability to measure what it is supposed to measure, should be considered when selecting relevant tests. It is important that coaches select tests that precisely represent the movement skills and the physical capacities they want to measure through screening and assessment, respectively.

Reliability is concerned with a test providing suitable measurement precision and consistency. This is important to ensure a test accurately characterises the athlete’s performance within an acceptable level of variability. Understanding the reliability and typical variation in a test allows coaches to determine if observed changes in performance have occurred due to an alteration in the athlete’s physical or movement capacity and so represent ‘real’ change, rather than measurement error. Error in the data recorded may represent biological (variability from the participant while performing a given protocol) or technical error (variability in measuring tools, such as the equipment used) and will vary depending on the test and the manner in which it is performed. The biological and technical error associated with tests can be reduced by standardising protocols. To achieve this, coaches should ensure the same testing equipment is used for each testing session and that the equipment is setup correctly and calibrated as required. Additionally, facilities, athlete clothing and footwear, time of day, the warm-up protocol employed and the instructions provided should be consistent across testing sessions, or large error in test results may be present.

Although access to reliability data is available in published literature, it is important to note that the skill level of the tester, the population sampled and subtle changes in the procedures may influence these values, resulting in the potential for the misinterpretation of findings. Therefore, it is recommended that coaches determine their own measurement error for each test with the population they are working with. A brief example is provided to demonstrate how typical error can be calculated for the calf raise test (described later in this chapter) performed by 11 track and field athletes with 7 days between testing sessions. Table 7.1 presents the scores for each athlete for test days 1 and 2, along with the test-retest difference. Typical error is calculated by dividing the standard deviation of the test-retest difference by V2 (Hopkins, 2000). Using the data from Table 7.1, typical error for the calf raise test is 1 repetition, indicating changes in calf raise test scores exceeding a single repetition likely represents a ‘real’ change in the strength endurance of the ankle plantar flexor musculature.

TABLE 7.1 Single-leg heel raise scores (number of repetitions performed) for 11 athletes from two separate testing days and the between-session absolute difference

Movement Screening

Movement screening involves analysing an athlete’s technical performance across a variety of tasks, with the aim of determining their level of competency. In turn, this provides an indication as to whether an athlete possesses the necessary skill to load the associated movement patterns. For example, an athlete who displays end range of motion spinal flexion during a body-weight squat prior to reaching 90° of knee flexion presents a movement fault relative to the performance criteria associated with the screen (see Table 7.2). If the athlete were to persevere with loading this pattern in an attempt to develop leg strength, injury risk may increase (Siewe et al., 2011) as the spines tolerance to compressive loading is diminished (Gunning et al., 2001) and shear forces are elevated (I'otvin et al., 1991). Instead, the athlete would be better served in addressing the technical issues by removing any functional limitations that exist (e.g. restricted ankle and hip mobility) and devoting time to develop the hip-back disas- sociation sequencing required to demonstrate a competent squat technique.

Selecting Movements to Screen

Movement screening can be a time-consuming process, taking up to 30 min to complete for each athlete (Bennett et al., 2019). As coaches also often perform a biomechanical analysis (i.e. gait analysis), range of performance tests (i.e. Й0_2тах test) and physical capacity assessments, time is a valuable commodity and should be considered when designing a test battery. Movement screens should therefore be filtered to include only movements that qualify an athlete for loading in specific exercises that are likely be prescribed, and can therefore directly inform the training process.

Specificity for exercise selection is an accepted principle for the transfer of training (Brear- ley and Bishop, 2019). Less commonly appreciated is that movement screens should also be specific to the coaches’ intended outcome (i.e. movement quality during exercises that will be loaded) and possess high construct validity. This is particularly relevant when attempting to infer movement quality for one exercise when screening other movement patterns that may appear visually similar. For example, peak knee abduction angle during double-leg squatting is not associated with the same measure during double-leg jump-landing performance (Donohue et al., 2015). It is likely that this occurs due to the task demands being markedly different. In this instance, double-leg squatting presents as a mobility challenge, with considerable sagittal plane motion at the hip, knee and ankle joints required to achieve a deep squat position (Hemmerich et al., 2006), whereas jump-landings require greater eccentric strength to attenuate the larger peak forces (Montgomery et al., 2012). Therefore, if a coach wishes to determine competency for performing squatting and landings, movement screens for each pattern should be included in the testing battery.

When selecting movements to screen, the coach should also consider the way each is performed. Even within the same movement pattern (e.g. squat), slight changes in the constraints related to the task can result in a misleading interpretation of an athlete’s skill level relative to a specific exercise. For example, screening the overhead squat with the feet facing directly forward is commonly used during movement screens (e.g. Cook et al., 2014). However, this test offers little insight into an athlete’s ability to squat with the arms across the chest and the feet in a self-selected position (McMillian et al., 2016). As the primary aim of movement screening is to determine the runner’s readiness for loading within the exercise, the technical features

of the movement screen should be similar to the associated technical model. It is therefore suggested that coaches carefully consider the constraints imposed on the athlete during the performance of the movement screen.

The coach’s approach to training and developing general physical qualities to improve running performance should also assist coaches in selecting relevant movement patterns for screening. In some instances, this may require an assessment of regions of the body that have no direct functional relationship to distance running. For example, coaches that choose to improve a runner’s explosive strength through the prescription of weightlifting exercises (e.g. variations of the snatch, clean or jerk) should screen movements that focus on the mechanics of the spine (Howe and Read, 2015) and shoulder complex (Howe and Blagrove, 2015). In this instance, assessing the mobility and coordination of these segments during an overhead movement will inform the coach of the athlete’s ability to achieve a successful overhead barbell position in preparation for the snatch and jerk exercises and their derivatives. Therefore, a coach’s philosophy and their preferential methods to develop strength qualities should also influence the selection of movement screens to inform the training process.

Based upon the physical demands of distance running, and the associated S&C provision that will be required to target ‘sport relevant’ training adaptations (see Chapter 14), the following movements could be considered for inclusion as part of a comprehensive screening battery. The list presented in the next section should be regarded as a menu for coaches to choose from, with only a small selection of movements being required in most instances. The decision as to what movements to select should be based upon the needs of the athlete, relevant situational context and potential constraints in the training environment, and the programming strategies the coach wishes to employ.

Administering a Movement Screen

A major limitation of movement screening is the requirement to assess numerous components of the performance criteria simultaneously. As such, the level of agreement has been shown to be poor between a tester evaluating movement competency in real time and objective measurements recorded using 3D motion capture (Whiteside et al., 2016). Although real-time movement screening can produce reliable results (Onate et al., 2012), it is recommended that coaches use video analysis when possible to improve accuracy and allow visual test/re-test comparison that may further guide training provision and can act as an effective feedback tool for the athlete. If logistics require coaches to screen in real-time, it is recommended that for each repetition, only one variable from the performance criteria is assessed. This will result in the number of components included in the performance criteria determining the minimum number of repetitions performed for each screen (Gould et al., 2017). If this approach is employed, coaches will avoid the error associated with screening movement with performance criteria’s, including several components across only three repetitions in real-time (Whiteside et al., 2016). However, this practice is only appropriate if the athlete has been sufficiently familiarised with the movement pattern and the strategy' demonstrated is consistent.

Based upon the need to obtain accurate results from a movement screen, coaches should adhere to the following process:

• 1. For each screen, a camera should be set up at a distance that captures the entire movement, while accounting for perspective and parallax error (Payton, 2007). It is recommended that the capture area is marked out for consistency and the distance the camera is positioned from the athlete is measured and recorded to ensure replication for test/re-test purposes. Practically, 3.5 m between the camera and the athlete has been employed for reliably screening movement using 2D video analysis (Howe et al., 2020).
• 2. For screens that require footage in both the sagittal and frontal plane, coaches can either use two cameras to record footage simultaneously, or, if only a single camera is available, the athlete should perform clusters of repetitions at different angles to the camera to allow for footage to be recorded in various planes.
• 3. Athletes should wear the same footwear they expect to regularly train in and clothing that allows for anatomical landmarks to be observed (e.g. shorts to mid-thigh length), whilst allowing unrestricted movement.
• 4. Standardised instructions of how to perform the task should be given using a script that includes only relevant information. A demonstration should also be provided to ensure athletes have a clear understanding for how the task should be performed. See Table 7.2 for a suggested script for each screen.
• 5. A minimum of three repetitions should initially be performed by the athlete to allow adequate familiarisation. This should be repeated until the athlete reports they are comfortable with the movement and the coach is confident there is sufficient consistency between repetitions to ensure reliable results are recorded. Coaches may need to use this time to reinforce specific test instructions.

Performance Criteria

Movement screens commonly employ a scoring system that allows for a composite score to be calculated through a range of screens (Bennett et al., 2017; Frohm et al., 2012). However, where individual screens may have the potential to identify runners at greater risk of injury (Hotta et al., 2015), the use of composite scores fails to provide the same predictive value (Bring et al., 2018) and also lacks factorial validity (indicating the tests are largely independent of each other and do not screen generic abilities). Furthermore, a composite score fails to help coaches determine competency during each movement pattern. Instead, attention should be focused on the performance of individual screens and the movement faults that may present (Read et al., 2016) and as a result, a pass-fail criterion is suggested for each movement.

Once movements have been selected to screen, coaches must adopt a performance criterion, which athletes can be compared against. The criteria represent the technical features that the athlete should display, providing coaches with a clear guideline for how the movement should be performed. This requires coaches to clarify compulsory features for each screen, so the athlete can be cleared to ‘pass’ the screen and load the movement. Coaches should therefore filter their performance criteria to include features of the exercise technical model that are fundamental to ensure safe and effective performance of the movement. Table 7.2 presents a performance criterion for each screen presented.

Investigating the Cause of Movement Faults

Following the administration of a movement screen, coaches must determine whether the athlete displays acceptable technique. When an athlete performs a screen that matches all elements of the performance criteria, they have ‘passed’the screen. The coach’s interpretation should be that the athlete has demonstrated an acceptable level of movement skill and the pattern can be performed with suitable technique so that loading may commence.

When movement faults are present (the athlete fails to perform the movement in a manner that matches all elements of the performance criteria), they have ‘failed’the screen and a thorough investigation is required to establish the cause. Due to the complex nature of each movement, using a simplistic approach of equating a movement fault to a functional deficit in the neighbouring anatomical region (e.g. excessive flexion in the spine during the squat equates to weak spinal extensor muscles) in many cases, leads to inaccurate assumptions and unhelpful solutions in an attempt to solve the movement puzzle (Howe and Cushion, 2017). Such an approach in most cases results in the prescription of several corrective exercises that do not address the cause of the movement fault and, therefore, fail to improve movement quality. As time to train is always limited, this strategy not only presents a potential waste of time and resources, but also restricts athletes from completing training that more effectively improves running performance. To avoid this pitfall, a problem-solving process should be implemented to determine the primary cause(s) of the movement fault(s). Figure 7.1 illustrates a four-stage model to systematically investigate the cause of movement faults.

Stage 1 involves having the athlete perform the movement screen with a ‘pass’ or ‘fail’ outcome as previously discussed. Stage 2 requires practitioners to coach the performance of the screen prior to further testing being administered. This allows coaches the opportunity to distinguish between whether a skill or capacity issue is causing the movement fault. If the athlete can pass the screen following time spent practicing the movement under the coach’s guidance, then the athlete is likely to possess the necessary capacities to perform the movement to the standards outlined in the performance criteria. For example, if an athlete performs the squat screen with excessive forward trunk lean, a restriction in ankle dorsiflexion range of motion may be the culprit (Conradsson et al., 2010; Fuglsang et al., 2017). However, if the athlete is made aware of the strategy' they are employing and can self-correct without compromising other aspects of technique, enough ankle mobility is present relative to the task demands. In such instances, the skill to coordinate the movement was the underlying cause, with the athlete requiring a more detailed mental template for how the movement should be performed.

FIGURE 7.1 A four-stage model to systematically investigate movement faults

This process will save a coach’s valuable time by decreasing the demand for additional tests and avoid unnecessary prescription of corrective exercise modalities.

In most cases, coaching an athlete how to perform a movement (that may be performed directly after the screen or in a separate session) should last only a few minutes to determine whether a skill issue is present. This suggestion is supported by evidence that drastic changes in technique can occur following basic instruction. Frost et al. (2015) showed performance on a movement screen significantly improved when firefighters were informed of the performance criteria for each movement. However, coaching is more than just explaining technical models. Therefore, packaging information through verbal feedback, demonstrations and the development of kinaesthetic awareness will likely result in greater improvements in movement quality, and in many cases, less time than it takes to explain the performance criteria of a screen. For more information, readers are referred to Cushion et al. (2017).

Stage 3 of this process should guide coaches as to what capacities may be lacking and, as a result, what additional assessments should be employed in Stage 4. This is accomplished by manipulating elements of the movement task to gain insight into the underpinning cause. Although an infinite number of options exist, this stage does not need to be extensive or overly complicated. A simple example of how a movement pattern can be manipulated to help identify the primary cause can be to adjust the load or starting position. For example, if an athlete demonstrates a dynamic knee valgus during the single-leg squat screen that does not improve following coaching, weak hip abductor muscles (Crossley et al., 2011) or restricted ankle dorsiflexion range of motion (Dill et al., 2014) may be the cause. In this instance, the coach can manipulate the task in several ways. One option could be to have the athlete perform the movement with both feet together to unload the lower extremity (by using both legs to perform the movement) without changing the mobility demands. If the dynamic knee valgus is no longer apparent, a lack of strength is the likely culprit and the hip abduction strength test should be performed. However, if the dynamic knee valgus remains unchanged, ankle hypomobility may be the cause of the movement fault. This working hypothesis can be further challenged by asking the athlete to perform a single-leg squat with an elevated heel relative to the forefoot (e.g. placing a 2.5 kg weight plate under the heel) to provide the athlete with a greater capacity to translate the knee forward, imitating additional ankle dorsiflexion range of motion. If the athlete can now prevent dynamic knee valgus from occurring during the movement, a restriction in ankle mobility is likely present and the modified weightbearing lunge test should be performed. Additionally, this information can be used to provide an understanding of how the movement can be regressed. Consequently, Stage 3 develops efficiency in advancing the investigatory process alongside informing programming decisions.

Following manipulations of the task (Stage 3), the investigation process is progressed to Stage 4, where capacities are tested (e.g. mobility, strength, balance) using isolated assessments. For example, during bilateral squatting, the ankle joint dorsiflexes approximately 35° (Hem- merich et al., 2006; Swinton et al., 2012). If an athlete demonstrates restricted ankle dorsiflexion range of motion (i.e. < 35°), squat technique may be compromised (Conradsson et al., 2010; Fuglsang et al., 2017; List et al., 2013). Therefore, objective data obtained during isolated assessments of physical capacities provide information that can be directly compared to the demands of a movement pattern, supporting the interpretation of the findings. Table 7.3 presents isolated assessments used to establish mobility restrictions relevant to the squat screen described in Table 7.2. The interested reader should see Howe and Waldron (2019) for a range of mobility assessments that could be used to identify movement faults in other screens.

Test	Start position	Movement	Measurement
	Laying supine on the ground, with both knees extended and the arms by the athlete’s side.	The athlete is cued to maximally bring the knee of the test limb towards the ipsilateral chest, while bending the knee.	Prior to testing, the smartphone is zeroed against a vertical reference (e.g. wall). In the start position, a horizontal line is marked on the athlete’s thigh, 5 cm above the base of the patella. At the point of maximal hip flexion, the smartphone is placed proximal to the marked line at the point of maximal hip flexion.
	Athlete lays in a supine position with the legs extended. The test leg is flexed at the hip and knee to 90°.	The athlete maximally abducts at the hip (moves the knee away from the midline of the pelvis) while the coach stabilizes the pelvis, preventing rotation from occurring.	Prior to testing, the smartphone is zeroed against a vertical reference (e.g. wall). At the point of maximal hip abduction, place the phone on the medial surface at approximately mid-thigh.

(Continued)

Test	Start position	Movement	Measurement
	The athlete sits on the edge of a plinth, with the knees flexed at 90° and the lower legs freely hanging off the table. The non-test leg is placed over the lateral edge of the plinth by abducting the hip.	The athlete is instructed to maximally rotate the foot away from (hip internal rotation) the midline of their body, while maintaining a 90° flexed position at the knee.	Prior to testing, the smartphone is zeroed against a vertical reference (e.g. wall) and a horizontal line is made 10 cm above the inferior tip of the lateral malleolus. At the point of maximal hip internal rotation, the smartphone is placed directly proximal to the marked line.
	The athlete starts in a halfkneeling position, with the pelvis facing forwards and the trunk relatively upright (some forward lean is allowed). The test foot is positioned half a foot length ahead of the knee of the non-test leg, with the knee aligned directly over the foot on the test limb.	The athlete is instructed to reach the knee forward as far as possible, while keeping the knee over the foot, the heel down against the ground and the pelvis facing forward.	Prior to testing, the smartphone is zeroed against a vertical reference (e.g. wall). At the point of maximal ankle dorsiflexion just prior to heel-lift, the smartphone should be placed on the anterior bolder of the tibia distal to the tibial tuberosity.

Incorporating physical capacity assessments into a testing battery provides coaches with data to examine athletic performance qualities. In turn, this information supports decision-making throughout the training process. The following sections will discuss strength diagnostic and tissue capacity assessments that should be included in the initial athlete assessment and repeated regularly to evaluate progress.

Strength Diagnostics Assessment

Muscular strength plays an important role in the development of the distance runner, significantly contributing to improvements in performance-related measures (Blagrove et al., 2018a) and is associated with reduced injury risk (Lauersen et al., 2014). For the assessment of strength qualities, trunk and lower extremity force production during multi-joint and single-joint tasks provide a global and local indication of neuromuscular capabilities respectively. Table 7.4 illustrates suggested strength assessments, along with equipment requirements and procedures. Table 7.5 provides normative data to support the interpretation of test results (where appropriate).

Maximal Strength

Maximal strength, defined as the maximum force an individual can produce irrespective of time (Tillin and Folland, 2014), is measured directly using specialised equipment (i.e. force platforms and racks). The isometric mid-thigh pull is an example of a test that is commonly used that provides valid and reliable measures of an athlete’s peak force development (De Witt et al., 2018). A simple alternative when this equipment is not available is the weight an athlete can lift during an exercise for a specific number of repetitions (Verdijk et al., 2009). Coaches can choose to use either the maximum (concentric) load that can be lifted for a single repetition (e.g. 1 repetition maximum; RM) or a set number of repetitions (e.g. 5 RM testing) to determine maximal strength levels. However, fewer than 10 repetitions should be selected so as to provide an accurate measure of maximal strength (Reynolds et al., 2006).

A key consideration when performing RM testing, irrespective of the number of repetitions performed, is the athlete’s skill level on the exercise. To measure leg extensor strength, a variation of the free weight squat exercise is commonly used. However, some athletes do not possess the necessary skill to test maximal strength during the movement pattern (something that would quickly be examined through an appropriate movement screen). As an alternative, coaches may choose to use less complex movements to determine leg extensor strength capabilities. For example, the leg press may be an ideal option for a distance runner as it reduces the demand on the spinal extensor musculature and therefore provides an isolated measure of leg extensor strength. Furthermore, unilateral testing of each leg provides an opportunity' to measure limb symmetry. If an athlete presents with no experience of performing resistance training, coaches may choose to delay maximal strength testing until competence in technique under load has been demonstrated.

Explosive Strength

Explosive strength is defined as the maximum force an individual can produce relative to time and is commonly represented as rate of force development (Tillin and Folland, 2014). Explosive strength has been shown to improve distance running performance and maximal sprint speed

Note: RM = repetition maximum.

TABLE 7.5 Normative data for strength diagnostic and tissue capacity assessment

Note: RM = repetition maximum; BM = body mass.

(Rarmrez-Campillo et al., 2014). Measurement in practice commonly includes a variety ofjump tests, with peak jump height during a countermovement jump providing an accurate representation of explosive strength (McLellan et al., 2011) and leg power (Nuzzo et al., 2008). However, valid measures of jump height have traditionally required expensive equipment (i.e. force platform or contact mats) that many coaches may not have access to (Buckthorpe et al., 2012). With advances in technology, smartphone applications can now be used to accurately measure jump height (Balsalobre-Fernandez et al., 2015). Therefore, jump performance can be assessed across a range of tests using measurement tools accessible for all coaches at a low cost (< /(10).

Reactive Strength

Reactive strength is defined as the ability to effectively transition rapidly from an eccentric to concentric muscle contraction utilising a stretch-shortening cycle (Flanagan et al., 2008), and it represents an athlete’s plyometric quality. As distance running involves cyclical stretchshortening muscle actions, it’s unsurprising that enhancing reactive strength improves running performance (Ramirez-Campillo et al., 2014; Spurrs et al., 2003). The most common measurement is the reactive strength index (Flanagan et al., 2008), calculated by dividing either jump height or flight time by ground contact time during a plyometric rebound task, e.g. drop jump from a specified height (e.g. 0.3 m) or repeated vertical hopping. As with other vertical jumping tests, specialised equipment has traditionally been a necessity to record measures of reactive strength. However, reactive strength index can also be calculated reliably using smartphone applications (Haynes et al., 2019).

Tissue Capacity

During running, the trunk and lower extremity joint segments are repetitively loaded with each ground contact (Novacheck, 1998). In order to avoid maladaptation occurring and reduce the risk of injury (Cook and Docking, 2015), the muscles surrounding these joints must possess a high load tolerance. Tissue capacity refers to the ability of a musculotendon unit to produce force and tolerate load (Cook and Docking, 2015). Assessments of tissue capacity can provide insight into a specific structure’s strength capability through single-joint movements where a prolonged time under tension is the goal of the task. As a result, commonly used assessments require individuals to perform a task for a maximal number of repetitions (Dennis et al., 2008) or hold a certain position for as long as possible (Leetun et al., 2004). Although these tests of strength endurance will provide only a relative indication of maximal strength levels (Reynolds et al., 2006), they require minimal equipment, are simple to administer and provide reliable results (Dennis et al., 2008; Freckleton et al., 2014; Waldheim and Li, 2012).

Key areas to test for capacity are those associated with injury risk and performance in distance running, such as the trunk (Leetun et al., 2004), hip (Malliaropoulos et al., 2012) and calf regions (Hebert-Losier et al., 2009). For example, the strength of the calf musculature is associated with lower limb injuries (O’Neill et al., 2016) and performance during maximal sprinting (Mock et al., 2018). As maximal sprint speed has been shown to be a determining factor in distance running performance (Sinnett et al., 2001), developing strength qualities in the calf musculature is an important consideration.

Equally, tissue capacity' assessments of the hip musculature should also be of interest. Hip abduction strength has been correlated with dynamic knee valgus during running in both injured (Dierks et al., 2008) and healthy individuals (Heinert et al., 2008). Consequently, reduced hip strength has been suggested as an injury risk factor for running-related injuries (Mucha et al., 2017). Furthermore, high levels of hip abduction strength have been shown to increase a novice runner’s resiliency to injury when beginning a structured running programme (Ramskov et al., 2015). Unfortunately, testing hip abduction strength requires equipment that a coach may not have access to (i.e. handheld dynamometer). However, poor performance on the single-leg squat screen following coaching, and in the absence of an ankle mobility restriction, likely indicates hip abductor weakness and can be used as a surrogate measure (Crossley et al., 2011). Additionally, the side bridge test relies on lateral trunk and hip abduction strength and consequently is moderately related to hip abduction strength (Leetun et al., 2004). Therefore, coaches can determine whether an athlete presents with weak hip abductors by analysing their performance across several relevant tests. Table 7.4 provides an example of tissue capacity assessments that should be administered, while Table 7.5 displays normative data, and these can be used to support coaches’ decision-making processes.

Summary

Movement screening and physical capacity assessments are a fundamental component of the coach’s toolkit and should be considered a non-negotiable for use with distance runners. Data collected from these tests provide insight into an athlete’s physical profile and should be used to directly influence the training process. Specifically, movement screening allows coaches to determine an athlete’s level of preparedness to load relevant movement patterns. This process should be tailored to the athlete’s individual needs and the exercises selected to form part of a strength training programme. When movement faults are identified, the four-stage investigatory process presented in this chapter provides a framework for coaches to detect whether a skill or capacity deficit is the primary cause of the suboptimal strategy. Physical capacity assessments should also be administered to determine if the athlete possesses the requisite strength qualities. Examples include measurement of an athlete’s maximal, explosive and reactive strength using a variety of strength and jump assessments. Tissue capacity testing also provides useful information regarding a muscle or muscle group’s ability to produce and tolerate force and may be helpful in identifying areas that are vulnerable to injury.

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