An important point of this rationale, perhaps crucial in its understanding, is to realize the extreme importance of efficient movement control for fall avoidance. On the one hand, impaired movement control can lead to falls during daily activities [33]. On the other hand, inefficient movement is metabolically expensive, meaning the onset of fatigue will be faster and the subject will be less able to perform daily living tasks [34]. Thus, improving movement means not only an improvement in performance and achievement of the task objective, i.e., efficacy, but also regarding its economy, i.e., efficiency. Effective and efficient movement, i.e., the definition of movement quality, depends on two fundamental capacities, namely stability and joint mobility [35,36]. Joint mobility is the ability to reach the required joint position for effective and efficient movement performance [37], while stability can be divided into postural and joint stability. Postural stability is the ability of the entire body to preserve its state of tendency towards equilibrium using its own means of motor control, whereas joint stability results from the motor ability to control the elements that act on each joint complex in order to maintain the proper angular position, providing reliability of execution [38]. Evidently, these two stabilities are interdependent since both are controlled by the central nervous system. In fact, the central nervous system controls joint mobility as well as postural and joint stabilities through three distinct but interdependent levels: higher level—cerebral cortex; middle level—brain stem; lower level—spinal cord [39]. The cerebral cortex controls the more complex voluntary movements, and the brain stem contains the great circuits that control postural stability and many of the stereotyped body movements [39]. The reciprocal innervation mechanism is an important process of the spinal cord movement control, coordinating the actions of agonist and antagonist muscles [40]. This mechanism is dependent on the quality of proprioception, a subcomponent of the somatosensory information that includes the afferent information arriving from the mechanoreceptors located at the periphery, i.e., Golgi tendon organ, neuromuscular spindle, and joint receptors [39]. This information is integrated into the spinal cord in order to control joint mobility and joint stability [40]. Still, this information also arrives at the higher levels of the central nervous system, namely the brain stem, which is quite essential regarding postural stability control [41]. Postural stability control, at the brain stem, is also dependent on vision and vestibular information; however, the information from peripheral mechanoreceptors is the most important from a clinical orthopaedic perspective [39]. In this way, proprioception has an important role in joint mobility as well as in postural and joint stabilities [28,41]. Proprioceptive exercises aim to improve the efficacy of the afferent feedback, in order to attain functional segment control and to achieve appropriate neuromuscular control of the muscles encompassing joint complexes [42]. They distinguish themselves from others by a greater ability to stimulate and enhance proprioception and somatosensory function. Thus, proprioceptive training programs may be an efficient tool to improve the agonist/antagonist muscle communication [42]. According to a systematic review that investigated the effectiveness of proprioceptive exercise programs for improving motor function [43], programs lasting 6 or more weeks can lead to improvements in proprioception and somatosensory function. Nonetheless, the optimal dose–response of this type of exercise is yet to be defined due to the enormous variability and lack of detail observed in the various studies concerning the training parameters, e.g., weekly frequency and workout duration. Despite this fact, it is widely accepted that stimuli applied to nervous structures during exercise will be more effective in conditions of absence of fatigue [44]. Moreover, the American College of Sports Medicine (ACSM) postulated that proprioceptive training is effective in reducing and preventing falls if performed 2–3 times/week [2].

Since exercise programs should aim to improve movement, namely through improving joint mobility and stability, it is essential to realize this is associated with the development of processes that underlie motor control, with the neuromuscular system being the key structure for all these processes. In this way, it is necessary to understand that muscles are just the “workers” and movement quality depends mainly on neuromuscular coordination, which takes place at two different levels, i.e., intramuscular coordination and intermuscular coordination. On the one hand, the central nervous system modulates the duration and intensity of activation of each muscle involved in the movement through intramuscular coordination, and on the other, ensures the combined and complementary intervention of the various muscles involved in the movement through intermuscular coordination [45]; muscular work is completely dependent on this control by the central nervous system. Given the above, it is not surprising that exercise prescription should be founded on improving movement patterns. Wickstrom was one of the first to define the basic movement patterns: walking, running, jumping, throwing, catching, striking, and kicking [46]. The author’s perspective was quite focused on the field of motor development during childhood. Since then, other authors have also presented their perspectives on this issue; however, more recently, two views have stood out, namely those of Santana and the Gray Institute [47,48], both focused on exercise prescription. Thus, the Gray Institute defines the following movement patterns: lunging—action of taking a step in a certain direction and returning to the starting position; squatting—action of squatting and returning to the starting position; jumping—action of jumping; reaching—action of reaching an object; lifting—action of changing the vertical position of an object; pushing—action of pushing an object; pulling—action of pulling an object; gait—action corresponding to locomotion, walking, or running. On the other hand, Santana classifies human movements into four movement pillars: locomotion, level changes in the subject’s centre of mass, pulling and pushing with upper limbs, and rotations. Locomotion is one of the most basic movement skills and is essential during daily living activities. Level changes are characterized by movements of the trunk or lower limbs, or a combination of both, that vertically displace the centre of mass. Pulling is any movement that brings the elbows or hands inward or toward the main line of the body. Pushing is any movement that brings the elbows or hands outward or away from the main line of the body. Finally, rotation is the most important pillar concerning daily living activities, involving movements that occur in the transverse plane. Both approaches postulated that exercise programs should be prescribed based on these movement patterns. Although any classification of movement patterns is valid and applicable to training, Santana’s proposal is easier to implement from the point of view of training organization and planning.

Santana also presented the concept of functional strength, which was defined as the amount of strength a subject can use during daily living activities and, according to the author, the most important strength to develop regarding functionality in everyday tasks [47]. According to other authors [49,50], functional strength training should focus on the quality of the movement pattern and treat functional movement as a priority. Therefore, exercises that aim to increase functional strength should be prescribed with low loads and with a focus on monitoring movement quality. Several research works studied the effects of this type of training and found improvements regarding joint mobility, postural stability, strength, and power in untrained young girls [50]; joint mobility, postural stability, and power in young tennis players [51]; agility, strength, and power in young adults [52]; postural stability and coordination in trained young males [53]; postural stability in young adult soccer players [54]; postural stability and strength in young adults [55]; joint mobility and postural stability in middle-aged and elderly adults [49]; strength, gait speed, and functional capacity in disabled elderly [56]; gait spatial and temporal parameters in elderly with dementia [57]. On the other hand, some of these studies found superior benefits of a functional strength training program when compared with a traditional strength training program concerning joint mobility, postural stability, strength, and power [50]; joint mobility, postural stability, and power [51]; agility, strength, and power [52]; postural stability and coordination [53]; gait speed and functional capacity [56]. Finally, according to Santana, it is important to develop functional strength through exercises for the four pillars of movement.

The National Academy of Sports Medicine (NASM) postulated that exercise progression with the elderly should be slow, well monitored, and based on postural control [58]. Any workout session, especially with the elderly, must consider the following structure: warm-up; the main part; cool-down [2,58]. During warm-up, it is vital to prepare the elderly for the upcoming movements of the main part of the session. In this way, active stretching, i.e., range of motion achieved using the strength of the antagonist muscles of those that are stretched [2], is an essential warm-up exercise to activate the nervous system [59]. During the main part of the session, exercises should be prescribed in order to achieve the stimuli defined for the workout session [2,58]; improving the gait biomechanical parameters related to falls and the four movement pillars, i.e., locomotion, level changes in subject’s centre of mass, pulling and pushing with upper limbs, and rotations. According to the most recent ACSM guidelines [2], strength training in the elderly should have a frequency of ≥2 workouts/week, 8–10 exercises/session, ≥1 set/exercise of 10–15 repetitions, an intensity of 40–50% of the one repetition maximum or at a 5–6 level of a perceived 10-point physical exertion scale (for seniors who are starting a strength program). During cool-down, it is important to promote recovery and return the body to a pre-workout level [2,58]. NASM and ACSM suggested static stretching for this purpose [2,58].

As mentioned in the introduction, some gait biomechanical parameters have been related to the occurrence of falls in the elderly. A well-studied biomechanical parameter regarding tripping is minimum foot clearance (MFC), i.e., the minimum vertical distance between the lowest point of the foot of the swing leg and the walking surface during the swing phase of the gait cycle [16]; however, several studies used the toe as the reference point, defining the term minimum toe clearance. According to a systematic review [16], there seemed to be no differences in MFC values when comparing elderly fallers with non-fallers. Nevertheless, data from the same review showed that elderly fallers yielded a higher MFC variability—standard deviation used to assess variability. A previous study pointed out that the higher variability yielded by the elderly reflected impaired motor control and the consequent increased risk of trip-related falls (standard deviation was used to assess variability) [60].

Lower-limb kinematics is strictly related to two important events during gait, i.e., MFC and the heel strike [61]. As described in the previous paragraph, MFC is an event associated with trip-related falls, while the heel strike, i.e., the instant when the heel or foot makes initial contact with the ground [62], is an event related to slip-related falls [17]. In this way, higher heel horizontal velocity at heel strike may increase the potential for a slip-induced fall [17,62]. Moreover, the angle between the foot and the floor at the heel strike is another parameter associated with slip-related falls [17,20]. Therefore, an upper angle between the foot and the floor at the heel strike increases the risk of fall due to a reduction in the shoe–floor contact area and an increased braking impulse at landing [17].

Foot control is also quite vital regarding articular and postural stabilities during the gait stance phase [63]. This foot control can be divided into three important sub-phases with different aims each: (1) controlled plantar flexion sub-phase—to control the foot impact with the ground; it is strictly related to the heel strike event; starts at the heel strike and ends at the instant of occurrence of maximum plantar flexion; (2) controlled dorsiflexion sub-phase—to control the foot so that it remains stable and allows the body to move forward; starts at the end of the previous sub-phase and ends at the instant of occurrence of maximum dorsiflexion; (3) powered plantar flexion sub-phase—to control the foot in order to properly push the lower limb into a stable swing phase; starts at the end of the previous sub-phase and ends at toe-off [63,64].

Ankle stability presents itself as the crucial capacity during the controlled dorsiflexion sub-phase. Joint stiffness plays a key role in achieving adjusted joint stability during movement [65]. In order to determine joint stiffness, the literature presents dynamic joint stiffness (Nm/Kg/°) as the reference parameter [36]. Based on this parameter, non-faller post-menopausal women with rheumatoid arthritis yielded stiffer behaviour compared to fallers during the controlled dorsiflexion sub-phase [21].

The powered plantar flexion sub-phase is also an important period regarding the gait cycle [63,64]. The ankle power peak during this sub-phase can be used to differentiate fallers from non-fallers in post-menopausal women with osteoporosis [22] and with rheumatoid arthritis [23]: both faller populations yielded a lower ankle power peak. Furthermore, the ankle moment of force peak during the same sub-phase is also reduced in rheumatoid arthritis post-menopausal women fallers compared to non-fallers [23].

Elderly fallers, compared to non-fallers, also yielded different values of the gait spatial and temporal parameters, i.e., shorter step/stride length [24,25] and lower cadence [25], leading to a lower gait speed [24,25,26,27]; as well as a shorter single-support phase [25] and a longer double-support phase [24,25,27]. Furthermore, a higher variability in the spatial and temporal parameters has also been found in elderly fallers, namely in the following parameters: stride length [27]; step length and double-support phase [24]; swing time and stride time [18,27]. In the elderly, a lower gait speed, a shorter stride length, and a longer double-support time were clearly related to fear of falling but presented slight evidence of an independent association with prospective falls [60]. On the other hand, increased variability in the gait spatial–temporal parameters (i.e., gait speed, stride length, and double-support time) was related to prospective falls in the elderly but presented no relation to fear of falling. Thus, the variability in gait spatial and temporal parameters measured through the standard deviation can be an important parameter for recognising subjects at high risk for falls and for assessing preventive interventions.

In numerous daily situations, the elderly may need to take recovery steps in order to maintain their postural stability, e.g., when turning suddenly to the side while standing or being jostled in a crowd [66]. Therefore, a recovery step can be used to restore postural stability when that is lost during daily living activities demanding a standing position. From a biomechanical point of view, this strategy tries to maintain or recover the position of the centre of mass over the base of support. According to recent research [19], recurrent fallers yielded impaired kinematics during lateral step recovery responses compared to non-fallers, i.e., higher centre of mass displacement, longer step initiation duration, and longer step duration.

The increase in elderly functionality should encompass improvements in the gait biomechanical parameters mentioned in the previous paragraphs. In this way, strength exercise programs [31,32] as well as proprioceptive exercise programs [28,29,30] showed an ability to improve these parameters. According to a previous study [57], improvements in gait spatial and temporal parameters of the elderly with dementia were found as a result of a functional strength training program. The authors concluded that the exercise program may represent a model for preventing and rehabilitating gait deficits in the target group.