Browsing by Author "Lambert, Michael"

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    Balance and agility in mountain bikers: a reliability and validity study on skills affecting control in mountain biking
    (2021) Buchholtz, Kim Anne; Burgess, Theresa; Lambert, Michael
    Background Cycling is a popular recreational and competitive form of physical activity and method of transport. Cycling is broadly categorised as road cycling or mountain biking, and each form presents unique challenges and has different skill requirements. While cycling, in general, provides many benefits to both physical health and social behaviours, there are legitimate concerns about injuries related to both road and mountain cycling. Most of the available research presents the injury incidence in commuter or road cycling, with an apparent lack of evidence in mountain biking. The van Mechelen model of injury prevention outlines four stages in injury prevention research; the first stage investigates the extent of the injury and provides the basis on which the remaining stages depend. Based on the van Mechelen conceptual model, the broad aim of this thesis was to investigate acute injury epidemiology in mountain biking and the factors affecting bicycle control and falling. Investigations We performed a systematic review of the incidence of injury in mountain biking. Acute injury incidence ranged from 4% to 71% in cross-country mountain bike races. The causal indicators of bicycle control may include balance, agility and visual perception. In a pilot study, we developed novel tests to assess static bicycle balance and bicycle agility as measures of bicycle control. In the following study, we developed additional dynamic bicycle balance with four increasingly difficult levels. In this study, twenty-nine participants attended three days of repeated testing for reliability assessments of these tests. Participants also completed an outdoor downhill run. Performance in the balance tests were compared to performance in the outdoor downhill test to assess their ecological validity. All tests were assessed for reliability using typical error of measurement, standardised typical error, intraclass correlation coefficients, limits of agreement, effect sizes and repeated measures ANOVA's (with post hoc testing) analyses. The novel bicycle balance and agility were significantly associated with the performance in the outdoor downhill run (r=-0.51 to 0.78; p=0.01 to 0.0001). Cognitive and physical fatigue are factors that may contribute to loss of control of the bicycle. In our final study, we aimed to assess the effect of these factors on the performance in the novel tests. Rate of perceived exertion was significantly increased for all tests following physical fatigue (Cliff's d effect size= 0.27-0.40; p=0.001 to 0.037), but balance and agility performance were not affected. Cognitive fatigue had no effect on balance and agility performance. The fatigue induced in these protocols was insufficient to change performance in the bicycle-specific balance and agility tests. This indicates that either the fatigue protocols did not sufficiently replicate the fatigue experienced in mountain biking or that the tests are too blunt to be affected by the magnitude of fatigue in these protocols. Conclusion The overall incidence of injury in mountain biking is difficult to determine due to different injury definitions in the research. However, the available data clearly indicates an area of concern in sports and exercise medicine. We developed novel tests to assess the skill components of balance and agility on a mountain bike. The novel bicycle-specific tests are robust assessments of mountain biking performance and can be applied in clinical and research environments to determine bicycle control. Cognitive and physical fatigue did not affect performance on these novel tests. Based on the overall findings of our studies, we recommend that further research is conducted on the epidemiology of mountain biking injuries. The effect of fatigue on the novel tests needs to be investigated further using a combination of physical and cognitive fatigue.
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    Ergogenic aids used by ultra-marathon runners
    (2015) Gwilliams, Michael; Burgess, Theresa; Lambert, Michael; Bosch, Andrew
    Background: Athletes of all levels and abilities utilise ergogenic aids to enhance sporting performance. However, the extent of ergogenic aid use within the ultra-marathon running community in unknown and there is little available literature documenting characteristics of use among ultra-marathon runners. Aims and Objectives: The aim of this study is to describe the use of ergogenic aids in ultra-marathon runners. The specific objectives of the study were to: a) To obtain information on the use of ergogenic aids in ultra- marathon runners, with regard to the type of ergogenic aids used, and the pattern of use during training and competition; b) To determine ultra- marathon runner’s perceived benefits of the ergogenic aids; c) To determine the factors influencing the intake strategies of ergogenic aids; d) To explore the factors that may predict the use of ergogenic aids, such as age, gender level of competitiveness, training and competition history. Methods: This study had a descriptive correlational study design. Participants included male and female ultra- marathon runners between 25 and 65 years of age. Participants who did not give informed consent and who failed to meet the defined classifications of being an ultra-marathon runner and medical screening criteria were excluded from the study. Participants were recruited through electronic correspondence, running clubs and running-specific media platforms. A self-developed questionnaire was designed to obtain information on ergogenic aid use in ultra-marathon runners during training and competition, as well as to determine the runners’ pattern of use and their perceived effect of ergogenic aids. The questionnaire was available in English and Afrikaans, and explored both legal and illegal ergogenic aid use. A panel of experts reviewed and validated the questionnaire. The online questionnaire was anonymous; with all referring uniform resource locators (URLs) and internet protocol (IP) addresses of respondents hidden to ensure anonymity. Results: The final sample was comprised of 266 respondents (n=179 males; n=87 females). The mean age of participants was 44 ± 10. The mean number of ergogenic aids used per participant was 5 ± 2. Dietary practice (47%) was the most common ergogenic intervention, followed by supplementary aids (45%), and pharmacological aids (18%). No participants reported the use of illegal/banned ergogenic aids. The highest self-reported ergogenic aid used was s ports drinks (n = 213; 80%) followed by vitamins (n = 181; 68 %) and carbo-loading (n = 165; 62%). Participants tended to use ergogenic aid s predominantly during competition and less so during training. Seventy-nine percent of participants believe d that their chosen ergogenic aid improve d their performance, while 9% did not think their performance was improved, and 9% were uncertain. The most frequently perceived benefits of ergogenic aids were ‘delayed fatigue’ and ‘providing an energy boost ’. Self-experimentation /personal experience, fellow runners and books/magazines were the highest ranked factors influencing intake strategies of the participants chosen aids. Runners who had more than ten years of ultra-marathon running experience were approximately 50% more likely to consume sports drinks. Females were about two and a half times more likely to utilize vitamins as an ergogenic aid. However, evidence from the general population suggests that females have a significantly higher daily intake of vitamins compared to males; therefore this finding might simply reflect daily supplement use and not be specific to ultra-marathon runners. The use of vitamins was also dependant on the number of ultra-marathons performed; participants completing more than five ultra-marathons were almost twice as likely to use vitamins as those completing less than five ultra-marathons. Recreational runners were approximately one third less likely to undertake the dietary practice of carbo-loading than competitive runners. The number of marathons and the number of ultra-marathons completed conversely affected the use of increased protein. This study was unable to identify any descriptive, race or training characteristics that influenced the use of caffeine, medication, gels or electrolytes as ergogenic aids. Conclusion: The findings of this study demonstrated that the prevalence of use of legal ergogenic aids is high and often used simultaneously. This study was unable to identify the prevalence of use of illegal ergogenic aids. However, the inappropriate and potentially unsafe use for many legal ergogenic aids was identified. Participants also reported false performance beliefs, potentially indicating poor knowledge or understanding of the effects of ergogenic aids. A major challenge is the strong influence of personal experience and information from fellow runners on the choice of ergogenic aids. Runners are accessing information through social networking, interactions and possibly social media, rather than scientific resources. Educational initiatives, with a focus on peer-led education, are essential to encourage the safe and effective use of ergogenic aids. This study highlights the importance of collective responsibility of the running community, including regulators, administrators, health care professionals, coaching and support staff, and journalists and authors of books and magazines to ensure that runners are informed about the safe and correct use of legal ergogenic aids.
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    Interactions between training load, submaximal heart rate, and performance in endurance runners
    (2019) Johansson, Rebecca Elin; Lambert, Michael; Swart, Jeroen
    Background: The popularity of endurance running events has rapidly increased in recent years with more recreational runners entering the field. How recreational runners train is not well known. Understanding this and the relationship between training and performance in this group of runners is important for prescribing appropriate training to maximise performance and decrease the risk of injury. This forms the underlying theme throughout this thesis. Aim: The broad aims of this thesis were to better understand the ad libitum training habits of well-trained competitive recreational runners and to determine the relationships between performance, training load, and submaximal heart rate (HR) in this cohort. Methods: Five inter-related studies were performed to: 1) determine relationships between 56-km race performance and pacing (n = 7,327) in competitive recreational runners; 2) determine relationships between 56-km race performance, pacing, and training load in competitive recreational runners (n = 69); 3) determine the accuracy of GPS sport watches in measuring distance (n = 255); 4) develop a feasible and reliable submaximal running test, and 5) determine relationships between performance on a submaximal running test, training load, and submaximal HR in well-trained competitive recreational runners (n = 29). Main findings: A group of well-trained competitive recreational runners performed 44 ± 22 km/week (median ± IQR) in a six-month time frame while training ad libitum. This group had a wide range of inter-individual differences in training load performed even when considering participants who had the same relative marathon performance. The same group of well-trained competitive recreational runners maintained most of their training over a sixmonth period in a range of 0.81 – 1.14 for the acute: chronic workload ratio (ACWR). When the ACWR values reached > 1.50, it was mainly due to participation in endurance running races (> 21-km). When looking at relative weekly changes in training load, the maximum increase was 30% with only two participants having maximum increases of < 10%. The increases in load were predominantly short term (one to two weeks). Submaximal HR had a negative linear relationship with performance in 21% of the study participants. In those participants, poor performances were associated with a higher submaximal HR. Training load was only related to changes in performance in one participant. Conclusion: This thesis confirms that no single variable can provide the necessary information on how to adjust training load to maximise performance. Athletes, coaches, and sports scientists need to have a holistic view of stress exposure and how this affects the body. Although we can only speculate, when the participants had a poor performance it may have been due to factors such as lack of motivation, fatigue, mental stress, dehydration, and/or sleep deprivation. It is important for runners, coaches, and sports scientists to approach the training load – recovery balance as being unique for each athlete. Even in a homogenous group of well-trained competitive recreational runners, their ad libitum training load is widely varied and was not associated with performance or ability level. The balance should be adjusted over time based on the athlete’s symptoms.
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    Measuring tackle and ruck technique in rugby union
    (2020) den Hollander, Stefanus; Lambert, Michael; Hendricks, Sharief
    Background: Developing tackle and ruck technique is important to improve performance in matches and reduce the risk of injury. Little is known regarding valid tools to assess tackle and ruck technique in rugby union. The aims of this thesis were (1) to assess the validity and representativeness of the contact assessment tool, and (2) to identify factors which may affect the degree to which contact technique developed in training transfers to matches. Methods: Tackle, ball-carry and ruck technique of players competing at different levels of play were assessed in a two-on-two training drill using standardised technical criteria. Technique scores between levels of play were compared to assess the validity of the contact assessment tool, and contact technique scores assessed in training and matches were compared to assess the representativeness of the tool. Physical qualities and questionnaire data on the importance of technique to improve performance and reduce injuries were compared to contact technique scores assessed in training, to determine the effect of physical conditioning and player's knowledge on contact technique proficiency. Finally, tackle and ruck technique scores assessed in training and matches were compared to measures of match performance and contact related injuries. Results: Senior players scored significantly higher in the tackle, ball-carrier and ruck assessment than academy 1st and 2nd level players, demonstrating the good construct validity of the assessment tool. Contact technique scores were associated with performance outcomes in training and in matches, although technique scores in matches were lower than technique scores in training. There were no significant relationships between player's knowledge of the importance of contact technique and their contact technique proficiency. There were moderate to large associations between various physical qualities and tackle, ball-carry and ruck technique scores assessed in training. Players with better contact technique in matches performed better in matches, however, there were no meaningful correlations between contact technique in training and match performance or match related contact injuries. Conclusions: These findings demonstrate the validity of a tool to assess contact technique in rugby union with good representative learning design, however progressing the drill into less structured environments is recommended to further improve the representativeness of the assessment environment. Furthermore, the findings highlight the importance of contact skill training and physical conditioning to ensure skills developed in training are transferred to match performance.
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    Monitoring wellness, training load and neuromuscular performance: Implications for assessing athlete training status
    (2021) Lombard, Wayne; Lambert, Michael
    Background: Athletes training for peak performance have periods of systematic overload followed by recovery. The balance between overload and recovery is important to avoid unexpected fatigue or underperformance. The relationship between overload and recovery is unique for each athlete. Thus, programmes designed to monitor fitness and fatigue should consider the inter-athlete differences. Aim: The broad aim of the PhD thesis was to assess the relationships between various tools for monitoring fitness and fatigue in elite level athletes. Subjective and objective training/match demands, questionnaires to assess wellness and readiness-to-train as well as countermovement jump variables to assess neuromuscular performance were investigated within 4 inter-related studies. Methods: Four inter-related studies were designed to determine; 1) the validity and reliability of countermovement jump variables measured on a force plate in the laboratory; 2) the relationships between countermovement jump variables, responses to a wellness and readinessto-train questionnaire and exercise-induced fatigue in the laboratory; 3) the relationships between training load, responses to a wellness and readiness-to-train questionnaire and neuromuscular performance in elite level female field hockey athletes measured in a “realworld” situation, and 4) the relationships between these same variables for each athlete and whole team before, during and after international match play. Primary findings: The findings for each inter-related study were as follows; 1) Maximum force, rate of force development, jump height, flight time and time to maximum force, as measured on a force plate during a countermovement jump were valid and reliable. The typical error of measurement was defined for each variable. The validity and reliability were best in participants who had more strength training experience. In most cases the precision of the variables was sufficient to detect “small” changes. 2) Subjective measures (wellness questionnaire) were more sensitive to acute exercise-induced fatigue compared to objective measures of neuromuscular performance; 3) The relationship between variables differed between players. Multiple variables should be collected to better understand a player's subjective and objective fitness and fatigue status in response to subjective and objective measures of match and/or training demands; 4) Pre, intra and post-match related data should be collected to better understand individual player responses between matches. Variables such as jump height, rating of perceived exertion, total distance during the match, bodyload (a derived measure of the total external mechanical stress from accelerations, decelerations and change of direction) and subjective wellness should be considered when monitoring athlete training status. Conclusions: Firstly, there is no set standard battery of tools that can be used to monitor fitness and fatigue of athletes as the relationship between variables is not consistent between athletes. Variables such as jump height, rating of perceived exertion, total distance, bodyload and wellness responses should be considered in a monitoring system. Secondly, this thesis proposes the novel concept of “monitoring specificity”. This suggests that different tools, based on their responsiveness, should be used at an individual level. Thirdly, identifying which athletes are most sensitive to certain variables will reduce the “noise” within a team's monitoring system. This will enable better informed decisions to be made about the athlete's fitness/fatigue status.
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    Playing time of professional senior rugby players across all levels of South African rugby, 2007 -2012: implications for transformation
    (2014) Du Toit, Jacques; Lambert, Michael
    A single governing body to govern South African rugby was formed in 1992. This allowed for changes to governmental policies to South African sport, resulting in South African sport being fully representative of the population. The South African Rugby Union (SARU) therefore has a continual challenge to make rugby fully representative at both provincial and national levels. Previously rugby has been dominated by white players at all levels. The SARU has implemented various programmes in order to accelerate the development of players of colour. Previously the success of these programmes has not been evaluated because the players representing different ethnic groups have not been quantified in a systematic way. The aim was to quantify playing time and playing numbers of South African professional rugby players of different ethnic groups from 2007 to 2012 at all professional levels (Springboks, Super Rugby, Currie Cup and Vodacom Cup). Quantifying playing time and playing numbers was done to establish changes in profile of South African rugby players across the given time period. Thus the efficacy of the SARU programmes to accelerate transformation was indirectly evaluated. A further aim was to determine if there had been a change in ethnic profiles between the various rugby unions from 2007 to 2012.
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    Post-exercise oxygen consumption and heart rate recovery as possible measures of the homeostatic stress of an exercise bout Theresa Naomi Carol Mann.
    (2013) Mann, Theresa Naomin Carol; Lambert, Michael; Lamberts, Robert P
    Several methods have been used to quantify the internal training load of a bout of exercise. However, arecent novel approach to quantify the internal training load has been to investigate the dynamic returntowards resting homeostasis at the cessation of exercise. Objective and non-invasive methods ofmonitoring the return towards resting homeostasis include measures of heart rate recovery (HRR) andexcess post-exercise oxygen consumption (EPOC). However, the relative potential of autonomic- vs. metabolic-type recovery measurements to represent the internal training load or homeostatic stress of the preceding exercise bout has not been established. Therefore, the broad aim of this thesis was to investigate the magnitude of EPOC (EPOCMAG), the time constant of the EPOC recovery curve (EPOCτ),HRR within the first minute post-exercise (HRR60s) and the time constant of the HRR curve (HRRτ) as measures which might reflect the homeostatic stress of an exercise bout. It was hypothesized that a measure representing the homeostatic stress of an exercise bout could have the following possible applications; - to identify inter-individual variation in the homeostatic stress of a standardized exercise bout - to detect intra-individual variation in the homeostatic stress of different exercise bouts- to detect intra-individual variation in “readiness to train”, based on the response to a standardized exercise bout. Therefore, the investigations of this thesis aimed to assess the relative potential of EPOCMAG, EPOCτ,HRR60s and HRRτ in these different roles. The experimental work was divided into 4 studies.
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    Quantification of training load in junior provincial rugby union players
    (2020) Rust, Ruan; Lambert, Michael
    Study purpose: The objectives of the study were to measure external and internal load and recovery status of junior semi-professional rugby union players (n = 36) during the u/19 Currie Cup campaign. Methods: The monitoring period covered 280 days (July – October) and included phases divided into off-season, pre-season and competition. Twelve league matches were played during the competition phase. The variables associated with external and internal load and recovery status were summarised for each player and also compared to each other to establish relationships between these variables. Data were collected either daily (training load, subjective fatigue and recovery) or weekly (recovery heart rate) or during matches (mechanical load, physiological load and training load). Injuries were also recorded throughout the season. Results: The primary finding of this study was that the players' loads (arbitrary units; AU) (605293 AU), fatigue (4.51.3 AU) and recovery (14.12.3 AU) did not change significantly throughout the different phases of the season. Also, recovery heart remained similar throughout the different phases of the season supporting the pattern of the subjective data. There was no clear predictive relationship between training load, subjective fatigue and recovery prior to sustaining an injury (both soft tissue and musculoskeletal). Conclusion: This study questions the usefulness of a wearable device to measure training load (internal/external), particularly since the session rating of perceived effort(sRPE) is cost effective, quick and easy to implement and provides accurate information. Subjective training load and subjective fatigue did not predict injury in this cohort of players. However, these variables can be used as markers to guide training to ensure the conditioning status of the players remains similar throughout the season. In particular they enable individualised decisions to be made about each player, ensuring that load and fatigue in response to the load remain steady.
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    The agreement, reliability and accuracy of a subjective-rating for technique measurement in rugby union after video-based training
    (2018) Wulfsohn, Jason; Hendricks, Sharief; Lambert, Michael
    Background: Rugby union is a high-intensity, intermittent sport, characterised by numerous contact events, such as rucks, mauls, scrums, and tackles. Specifically, the tackle is the most common action to occur during a rugby game. Subsequently, the tackle (tackler and ballcarrier) is responsible for the highest number of total injuries during a season. The most effective tackle technique is associated with a lower risk of injury than poorly executed tackles. Considering the prevalence of tackles, their propensity to cause injury, and the link between safety and proper tackle technique, a tool for assessing individual tackling and ball-carrying technique would be useful for rugby union researchers and practitioners. In particular, the assessment of tackling and ball-carrying technique would aid in monitoring adaptations to training, evaluating training programs and the prescription of training, assessing player qualities, and predicting performance and identifying future talent. Objectives: The primary objectives of this study were 1) to determine if undergoing videobased training would improve the agreement, reliability, and accuracy of raters using a subjective-rating measure to assess contact technique in rugby union, and 2) to establish if a self-selected viewing pace resulted in improved agreement, reliability, and criterion-validity over a real-time pace. Methods: Data were collected from 30 participants, with no prior experience in rugby union, who were randomly divided into training and non-training groups. After completing the training or non-training visits, all participants conducted tackling and ball-carrying technique assessments in 4 subsequent visits. Participants viewed video footage of players tackling and carrying the ball into contact during a full contact rugby drill on a laptop computer. Participants assessed tackling and ball-carrying technique using the standardised list of technical criteria. Technical proficiency scores were calculated out of 12 for tackling technique and out of 10 for ball-carrying technique, respectively. Agreement and reliability of the assessments were measured using the proportion of observed agreement (Po) and Kappa statistics (K). Criterion validity (accuracy) was measured using the proportion of observed agreement (Po) by comparing the raters’ assessments to a criterion. Between groups comparisons for technical proficiency scores and accuracy were done with hypothesis testing and effect sizes. Results: Over the real-time and self-selected paces, the training group produced 61-73% (K=0.24-0.38, Fair) and 63-73% (K=0.12-0.17, Poor) inter-rater agreement for tackling and ball-carrying technique, respectively. The non-training group produced 61-72% (K=0.26-0.38, Fair) and 59-71% (K=0.15-0.19, Poor) inter-rater agreement for tackling and ball-carrying technique, respectively. Including both real-time and self-selected paces, the within session intra-rater agreement for the training group ranged from 71-84% (K=0.43-0.65, Moderate-Substantial) and 74-83% (K=0.39-0.48, Moderate) for tackling and ball-carrying technique assessment, respectively. Then, the intra-rater agreement for the non-training group ranged from 68-83% (K=0.40-0.62, Fair-Moderate) and 67-84% (K=0.31-0.55, Fair-Moderate) for tackling and ball-carrying technique assessment, respectively. In terms of between session reliability, over the real-time and self-selected paces, the training group achieved intra-rater reliability that ranged from 74-83% (K=0.50-0.62, Moderate-Substantial) and 72-82% (K=0.35- 0.45, Fair-Moderate) for tackling and ball-carrying technique assessment, respectively. The non-training group achieved intra-rater reliability ranging from 72-82% (K=0.46-0.59, Moderate) and 69-81% (K=0.33-0.48, Fair-Moderate) for tackling and ball-carrying technique assessment, respectively. The technical proficiency scores between the groups displayed variation, and in some cases it was statistically significant. Compared to the criterion scores, the training group produced observed agreement of 68% and 67% for real-time pace and 74% and 72% for self-selected pace on tackling and ball-carrying technique assessment, respectively. The non-training group produced observed agreement of 66% and 67% for realtime pace and 74% and 73% for self-selected pace on tackling and ball-carrying technique assessment, respectively. Conclusion: Whether trained or untrained, the individual should be able to produce the same results if the footage is assessed within the same viewing period (agreement) or over two separate viewings (reliability). The tool is accurate for both groups when assessing at real- time or self-selected paces, with the latter being more accurate. However, it would appear that the tool is insufficiently robust when it comes to agreement between different raters. Future research should explore the inter-rater dynamics of assessing tackling and ball-carrying technique.
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    The effect of carbohydrate ingestion on performance during a simulated soccer match
    (2013) Goedecke, Julia; White, Nicholas; Chicktay, Waheed; Mahomed, Hafsa; Durandt, Justin; Lambert, Michael
    Aim: This study investigated how performance was affected after soccer players, in a postprandial state, ingested a 7% carbohydrate (CHO) solution compared to a placebo (0% CHO) during a simulated soccer match. Methods: Using a double-blind placebo-controlled design, 22 trained male league soccer players (age: 24 ± 7 years, wt: 73.4 ± 12.0 kg, VO2max: 51.8 ± 4.3 mL O2/kg/min) completed two trials, separated by 7 days, during which they ingested, in random order, 700 mL of either a 7% CHO or placebo drink during a simulated soccer match. Ratings of perceived exertion (RPE), agility, timed and run to fatigue were measured during the trials. Results: Change in agility times was not altered by CHO vs. placebo ingestion (0.57 ± 1.48 vs. 0.66 ± 1.00, p = 0.81). Timed runs to fatigue were 381 ± 267 s vs. 294 ± 159 s for the CHO and placebo drinks, respectively (p = 0.11). Body mass modified the relationship between time to fatigue and drink ingestion (p = 0.02 for drink × body mass), such that lower body mass was associated with increased time to fatigue when the players ingested CHO, but not placebo. RPE values for the final stage of the simulated soccer match were 8.5 ± 1.7 and 8.6 ± 1.5 for the CHO and placebo drinks respectively (p = 0.87). Conclusions: The group data showed that the 7% CHO solution (49 g CHO) did not significantly improve performance during a simulated soccer match in league soccer players who had normal pre-match nutrition. However, when adjusting for body mass, increasing CHO intake was associated with improved time to fatigue during the simulated soccer match.
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    The what and how of video analysis research in rugby union: a critical review
    (Springer International Publishing, 2018-06-18) den Hollander, Steve; Jones, Ben; Lambert, Michael; Hendricks, Sharief
    Background Video analysis is a common tool used in rugby union research to describe match performance. Studies using video analysis range from broad statistical studies of commercial databases to in-depth case-studies of specific match events. The range of types of studies using video analysis in rugby union, and how different studies apply the methodology, can make it difficult to compare the results of studies and translate the findings to a real-world setting. In attempt to consolidate the information on video analysis in rugby, a critical review of the literature was performed. Main body Ninety-two studies were identified. The studies were categorised based on the outcome of the study and the type of research question, sub-categorised as ‘what’ and ‘how’ studies. Each study was reviewed using a number of questions related to the application of video analysis in research. There was a large range in the sample sizes of the studies reviewed, with some of the studies being under-powered. Concerns were raised of the generalisability of some of the samples. One hundred percent of ‘how’ studies included at least one contextual variables in their analyses, with 86% of ‘how’ studies including two or more contextual variables. These findings show that the majority of studies describing how events occur in matches attempted to provide context to their findings. The majority of studies (93%) provided practical applications for their findings. Conclusion The review raised concerns about the usefulness of the some of the findings to coaches and practitioners. To facilitate the transfer and adoption of research findings into practice, the authors recommend that the results of ‘what’ studies inform the research questions of ‘how’ studies, and the findings of ‘how’ studies provide the practical applications for coaches and practitioners.