In the case of deliveries to the head with maximum speed there was evidence of more association in the recruitment of upper thigh and upper body muscles in the initiation of the action within the group of boxers (see figure 4). Again the peak activity of the triceps brachii and flexor carpi radialis were closely coupled in the final phase of the punch delivery. When punch delivery was optimized for maximum speed the muscular recruitment was more variable within the group of boxers, as indicated by the distance from the linear line.The increased mean force of delivery when a punch to the head was delivered with maximal force relative to maximal speed was 1587N equivalent to an additional 38% force delivery. This was associated with an increased level of activity in the rectus femoris muscle of 27% as shown in table 2.Maximum force Maximum speed DifferenceDISCUSSIONValentino et al. (1990) considered differences in the level of muscular activity during boxing and reported notable recruitment of deltoid muscles when a jab (or straight rear hand) punch was performed compared to an upper cut. This research has demonstrated the significance to punch force generation of a linear recruitment of muscles originating from the legs, trunk, shoulders and arms in sequence has been demonstrated in this research. This supports the importance of a boxer having the correct ‘stance’ and ‘on-guard’ position in order to throw effective punches (Hickey, 1980). The relative importance of leg extension at the ankle, knee and hip involving the gastrocnemius, rectus femoris and biceps femoris muscles was notable especially in forceful punch delivery. This work supports the approach that boxing coaches should prioritise the development of sequential muscular recruitment when coaching the technical requirements of rear hand punching.CONCLUSIONA linear model of recruitment of the muscles under investigation applied best in the case of maximum force punches delivered to the body with the importance of early recruitment of the rectus femoris, gastrocnemius, and biceps femoris muscles in the initiation of punch delivery evident particularly when punches were delivered with an aim of maximum force. The punching force to the head was 38% greater when maximum force was a priority relative to when delivery was for maximum speed, and this was associated with increased activity of 27% in the large rectus femoris muscle involved in rear leg extension.Maximum punching force and speed starts with the recruitment of muscles in the legs and a pathway of force travels through the human body to the point of impact. Coaches should consider focusing on developing such muscular recruitment sequence patterns, especially with young boxers.