# Motion Technologies in Support of Fence Athletes: A Systematic Review
## 3 Results
### Technological Setup and Models  
Based on the results of the 35 included studies, shown in Figure 3, it emerged that Optoelectronic Systems (n = 23 [2, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29]) were the most popular technological setup in the analysis of fencers, followed by sEMG technology (n = 9 [10, 15, 30, 31, 32, 33, 34, 35, 36], IMUs (n = 4 [10, 37, 38, 39] and markerless systems, i.e., Kinect (n = 2 [38, 40]). The instrumental setups mentioned in the included articles were produced by different companies: Vicon motion capture systems (Oxford Metrics, Oxford, UK) consisted of a minimum of 6 cameras to 16 cameras, with a variable number of 2 force platforms, Kistler (Kistler Instrument Corp., Novi, MI, USA). Twenty-nine studies reported the use of tridimensional models: the most used ones were the Calibrated Anatomical System Technique (CAST) protocol (n = 4, [8, 9, 10, 24]) and Plug-In-Gait (n = 4, [10, 11, 12, 13]). Only one study [40] developed customized software for the Kinect sensor to compare two movement patterns and allow data to be extracted for predictive modeling purposes. [PERSON] and colleagues examined the kinematics of the lunge speed using 8 cameras, retro-reflective markers positioned in accordance with the CAST procedure, and 4 marker cluster systems [8]. The findings demonstrate that knee flexion in the rear extremity is a significant predictor, which suggests that the fencer sits low in their stance to generate power during lunge [8]. [PERSON] and colleagues used reflective markers placed on the foot, shank, thigh, pelvis, trunk, and arm. Three high-speed cameras were employed, one of which captured the markers' entire movement and course. The software then combines the information from the three cameras to produce the 3D coordinates; the speed lunge is calculated as the travel distance and time of the marker placed on the iliac spine of the armed side; this was greater for elite fencers than novice, as for the lunge distance and the trunk inclination [17]. [PERSON] and [PERSON] used an infrared device to measure the speeds of the foil, the pelvis, the elbow, the shoulder, the knee, the ankle, the heel, and the fingers on both sides. They calculated the maximum horizontal speed of the foil, the maximum vertical speed of the foil, the maximum horizontal speed of the pelvis, the horizontal speed of the foil at the time of impact, the vertical speed of the pelvis at the time of impact, and the maximum horizontal speed of the pelvis. From the maximum value, the horizontal speeds of the pelvis and foil slightly decrease over time. Additionally, time-varying marker curves were computed. Depending on the subject, the horizontal direction and angle of the foil velocity might vary by 8\({}^{\circ}\) to 20\({}^{\circ}\)[19]. The coordination of the upper and lower limbs was examined using the hip and lunge speeds [41]. [PERSON] and [PERSON] investigated joint angle, ground response forces, knee joint torque, and reaction force changes in the lunge movement of athletes and the causes of the knee joint using a high-speed infrared imaging system, camera, and three-dimensional lateral force platform [18]. Using a camera, the Peak Performance System, markers on the fingers, heel, ankle, knee, pelvis, shoulder, knee, wrist, hand, neck, ear, and sword, [PERSON] and colleagues described the biomechanics of fencing lunges. The results show that shorter subjects have trunk flexion and a greater lunge distance when their knee angle is smaller. For all subjects, the sword and leg moved at the same time. The sword's speed is constant if it has a single peak reaction time of 0.3 s, otherwise 0.5 s [21]. The capacity of the fences to attack and defend as swiffly as possible to win a tournament is another crucial component of fencing lunge. Two force platforms, a virtual plate, 24 cameras, 5 markers scattered across the screen, and 7 markings on the sword--4 on the bowl and 3 on the blade--were all utilized by [PERSON] and colleagues.