Updated Review of the Applied Physiology of American College Football: Physical Demands, Strength and Conditioning, Nutrition, and Injury Characteristics of America’s Favorite Game

Abstract

While there are various avenues for performance improvement in college American football (AF), there is no comprehensive evaluation of the collective array of resources around performance, physical conditioning, and injury and training/game characteristics to guide future research and inform practitioners. Accordingly, the aim of the present review was to provide a current examination of these areas in college AF. Recent studies show that there is a wide range of body compositions and strength characteristics between players, which appear to be influenced by playing position, level of play, training history/programming, and time of season. Collectively, game demands may require a combination of upper- and lower-body strength and power production, rapid acceleration (positive and negative), change of direction, high running speed, high-intensity and repetitive collisions, and muscle-strength endurance. These may be affected by the timing of and between-plays and/or coaching style. AF players appear to possess limited nutrition and hydration practices, which may be disadvantageous to performance. AF injuries appear due to a multitude of factors-strength, movement quality, and previous injury-while there is also potential for extrinsic factors such as playing surface type, travel, time of season, playing position, and training load. Future proof-of-concept studies are required to determine the quantification of game demands with regard to game style, type of opposition, and key performance indicators. Moreover, more research is required to understand the efficacy of recovery and nutrition interventions. Finally, the assessment of the relationship between external/internal-load constructs and injury risk is warranted.

Using K-means Clustering to Create Training Groups for Elite American Football Student-athletes Based on Game Demands

“…Using 2 seasons worth of data together did not bring forth clear representative clusters that resembled traditional "bigs, big-skills, and skills" groupings (Pincivero & Bompa, 1997) like the data from the individual seasons. A clear differentiation still exists between the group of WRs and DBs and the group of OLs and DLs as noted in previous studies (Fullagar et al, 2017), but the other positions do not seem to split up as uniformly. Using 4 clusters aids this dilemma by creating groups that can be loosely identified in Table 7 as "bigs" (cluster 2), "big-skills" (cluster 1), and "skills" (clusters 3 and 4).…”

“…The playstyle of the individual at these positions undoubtedly has a large effect on how they are clustered. This brings clarity to the idea of how different playstyles can affect the demands of positions (Fullagar, McCunn, & Murray, 2017), which is evidence that this tool could aid in The two resultant "skills" clusters were interesting as it suggests that the technique differentiated "covering," a job performed by DBs and sometimes LBs, and "route-running," a job performed by WRs and sometimes TEs, before it differentiated the demands of RBs and DLs in the "big-skills" group of k=3 displayed in Figure 3. This differentiation does not emerge until the dataset is clustered using 6 centers.…”

Prevalence and risk indicators of non-carious cervical lesions in male footballers

“…The laboratory assays indicated normal salivary parameters in those participants with NCCLs; therefore, these lesions seem related to excessive mechanical stress and not to erosive factors such as acidic beverages or brushing immediately after meals. Fullagar et al reported that footballers possess limited nutrition and hydration practices [ 42 ]. The level of cortisol of all participants was found normal.…”

Isokinetic Performance of Knee Flexor and Extensor Muscles in American Football Players from Brazil

“…Among typical non-contact injuries, anterior cruciate ligament (ACL) ruptures (1.00 injury/1000 athlete-exposures) 6 and hamstring strains (1.67 injury/1000 athlete-exposures) 8 have been associated with some athletes' intrinsic features, such as the muscle strength imbalance between hamstring and quadriceps muscles (e.g., hamstring-toquadriceps ratio) 9,10 and strength imbalance between preferred and nonpreferred limbs (e.g., bilateral asymmetry) 10 . Thus, AF teams from USA have increasingly invested in isokinetic dynamometry tests 3 .…”