Fig 1.
The flowchart of the questionnaire rounds including recruitment, the content of the questions, and the number of respondents to each round of the questionnaire.
SME—Subject matter experts.
Fig 2.
The count of SME (n = 42) responses in round one by A) level of professionalism and B) the rugby football code they indicated they work in.
For A) other refers to holding a position at Olympic-level sport (considered separate to amateur sport), and B) other refers to also working in an Olympic sport (e.g., track and field). SME were free to choose more than one level of professionalism (e.g., professional and semi-professional) and sport (e.g. rugby league and rugby union) if they worked across multiple roles or sports. Values within the bars are counts of SME responses, and cumulative count percentage is presented on the x axis.
Fig 3.
Count of SME who responded to “On what days relative to the match-day (MD), do you (or would you) consider it important to monitor to monitor the athlete’s fatigue state?”.
The SME were free to select more than one selection if they considered it important.
Fig 4.
The SME ratings (median ± interquartile range [IQR]) of A) importance, and B) feasibility to implement of the items which achieved consensus in round one of the Delphi questionnaire for the neuromuscular performance (NP), cardio-autonomic (CA), and self-reported (SR) domains. For importance, the scale ranged from 1 –not at all important, to 5—extremely important. For feasibility to implement the scale ranged from 1 –extremely difficult to 5 –extremely easy. If end of the IQR error bar(s) is not visible it is due to this being located at the median. N—Newtons, VAS—Visual Analogue Scale, W—Watts.
Fig 5.
The SME ratings (median and interquartile range [IQR]) of A) importance, and B) feasibility to implement of the items which achieved consensus in round two of the Delphi questionnaire for the neuromuscular performance (NP), cardio-autonomic (CA), and self-reported (SR) domain measures.
For importance, the scale ranged from 1 –not at all important, to 5—extremely important. For feasibility to implement the scale ranged from 1 –extremely difficult to 5 –extremely easy. If end of the IQR error bar(s) is not visible it is due to this being located at the median. N—Newtons, VAS—Visual Analogue Scale, W—Watts.
Fig 6.
A graphical representation of a post-match player fatigue monitoring system based on SME ratings for A) important and feasible measures and metrics. The fatigue monitoring system includes B) a ‘toolbox’ of items that achieved consensus and rated highly (≥3/5) for importance and feasibility to implement in the rugby football codes for objective (i.e. neuromuscular performance [32–34], cardio-autonomic [35, 36]), and subjective (i.e. self-report assessment [5, 37, 38]) domains. Items which achieved consensus and rated highly for importance but not for feasibility to implement are represented by the arrow linking to the box to the right of the Venn diagram. Included within the graphical representation are C) considerations for testing and analysing data for the domains of these measures and metrics (see [5, 32, 33, 35–40] for further assessment considerations. ECG—echocardiogram, PPG—photoplethysmography, rMSSD—square root of the mean sum of the squared differences in R-R intervals, RFD—rate of force development, RSImod—reactive strength index modified, and SDNN—standard deviation of all normal-to-normal intervals.