# Applying Force Plate Technology to Inform Human Performance Programming in Tactical Populations
## 1 Introduction
In addition to strength, measures of lower body power, such as the CMJ, are indicative of occupational performances involving strength, speed, agility, or power (e.g., maneuvering over obstacles, dragging, lifting, and/or carrying loads, and sprinting) [30; 31; 32; 33]. Moreover, load carriage requirements in tactical populations influence injury risk if not adequately accounted for via enhancement of muscular strength and power [34; 35; 36; 37]. Greater recognition of muscular strength's importance for occupational performance is prevailing [17; 28; 38], although many of the adopted tests have inherent limitations and degrees of injury risk due to innate fatiguability. Isolated single muscle group assessments via dynamometry are not ecologically valid measures of muscular strength, as a majority of movements in tactical environments involve coordinated recruitment of multi-joint, large muscle groups by the nervous system. Further, 1-3 repetition maximal testing elicits undue fatigue and requires excessive amounts of equipment and skill [39; 40], which makes this testing inappropriate for untrained/novice populations or those enduring fatigue from occupational demands. These testing characteristics motivated the exploration of alternative methods for maximal strength testing that are non-fatiguing, require less skill, and include coordinated actions by multiple large muscle groups. A main limitation of field tests of muscular power (i.e., CMJ) using only tape on the wall for total jump height), explained in detail elsewhere [41], is their inability to capture the neuromuscular strategies called upon to generate observed outcomes (i.e., jump height), which may be more responsive to training loads. In fact, when estimating power output,kinematic variables often explain the relationship between power and vertical jump height, such as countermovement jump depth [42], a metric that is also sensitive to neuromuscular fatigue [43]. Further, a field test of CM] only depicts the outcome, which fails to inform whether the individual requires improvements in force or velocity capabilities (or both) to maximize their structured training methods [44]. Thus, alternative strategies, namely, force plate testing, are encouraged for the purposes of objectively monitoring tactical personnel. Further, force plates provide an inside look into movement strategies and forces generated throughout various phases of a movement (i.e., eccentric and concentric phases) in addition to the outcome metric (i.e., jump height during a CM) or drop jump). When protocols are designed and implemented effectively, force plates are considered the most reliable method of measuring vertical jump height [45]. The increased confidence in data quality obtained from force plates provides practitioners with an actionable means of identifying instances of training adaptations [46], levels of resiliency to fatigue [43; 47], and risks for injury [48]. Furthermore, CM]'s can be conducted under loaded conditions (e.g., bar-bell, weighted vest, occupational-specific equipment) to ascertain occupationally relevant performance capabilities (i.e., meeting load requirements during tasks performed by fire-fighters, law enforcement, or military personnel) or maximal strength capabilities [49; 50]. Isometric strength testing of large muscle groups (e.g., isometric mid-high pull, IMTP) is another appropriate measure of maximal strength, as it is relatively simple to administer, time-efficient, less fatiguing, and possesses high degrees of reliability under standardized testing conditions [51; 52; 53; 54]. Although high sampling frequencies generated by force plates may allow force-time metrics to be more sensitive (than jump height) to changes in the neuromuscular status of an individual [55; 56; 57; 58], they also present a large amount of data and number of force-time metrics to choose from.