Motor development is the progressive construction of maneuvers and situations for which, by acquiring controlled movements, we achieve an efficient skiing motricity. This is observed in gravity control, the integration of balance adjustments, the acquisition of precision, and in the global and specific movements’ control, among other aspects.
At the beginning, our motor behavior is based mainly on reactions, i.e., automatically reacting to each presented stimulus. As conscious movements integrate, these reactions decrease as we replace them by elaborated actions.
Motor Development and Motor Control Tendencies in Ski Learning
Although these are principles observed in children’s motor development, there are also noticed in adult ski learning due to the tendency to repeat them in new learning situations regarding motor control development.
- The cephalocaudal tendency relates that movement control gets progressively from head to feet. When we were beginners, also during present imbalanced situations, we tended to stabilize our head before we could control the skis with our feet.
- In the proximodistal tendency, our movements are controlled from the center to the periphery. We control our head before our arms, and then hands and poles. For example, as beginners, we were prone to maintain our forearms near the trunk with our hands up. Later on, in a way we better controlled our balance while sliding, we located our hands forwards, slightly downwards, and separated from our body in a more efficient manner.
- Flexor to extensor muscles tendency consists that, as flexor muscles develop earlier, we tended first to shorten them by contracting and then releasing them by stretching. An example is given when holding poles: at the beginning, holding them is characterized by being overly tight, elbows bent, forearms towards the trunk and poles lifted up, but later we relaxed by extending arms muscles to place them down and backward while holding them with less effort.
- The global to specific masses indicate our tendency to use bigger muscles controlling gross motricity first referred to global movements of large muscle groups to control posture and balance mainly. Then we develop fine motricity referred to specific smaller muscle movements as the ones of our feet or hands for precise edges or poles control.
Motor Skills
A motor skill is the ability to perform particular movement types. Learning how to ski is to become skilled at adapting familiar movements, or from other sports, to the new environment, i.e., to the slippery ground and to the supporting surface inclination. Motor skills adaptation speed to novel situations will depend on our sensorial development.
Motor Execution
In motor execution there are three phases:
- The preparatory phase which we do before any action by stabilizing our trunk.
- The agonist phase where we perform a specific action.
- The antagonist or final phase, where we slow down the agonist movement.
According to the theory of Ronald Marteniuk, performing a motor act involves three successive mechanisms.
- In the perceptual mechanism, we question ourselves what is happening via sensory organs providing information about the environment and our body, selecting the most relevant giving them a meaning. It is the phase in which we summarize internal and external conditions submitted to the deciding mechanism.
- In the decision mechanism, we deliberate what to do, choosing one of the available solutions deciding the most appropriate for the situation, analyzing it and programming our movements in relation to the determined action.
- The executive mechanism refers to how to execute what was decided (the motor response). In this phase, we perform the planned movements. The performing speed (fast or slow) depends on perceptual and decision mechanisms. In beginner levels, the three mechanisms are applied, while in expert skiers, due to experience, they tend to use the perceptual and executive mechanisms. This avoids decision-making waiting time, directly associating perception with the response, which is called motor anticipation.
In summary, once initiated the movements for a direction change, skin, muscles, and joints signals pass by the spinal cord reporting the execution state of our previously defined motor plan. During turning, these signals are compared with our motor planning which was sent to the somatosensory cortex and thus we sense if our performance is according to what we imagined.
With training, an execution automated level will arrive in which we perform our actions in a simple and harmonious manner and with minimum attention, looking for motor agility since any form of clumsiness will make our skiing inefficient.
In optimum motor performances, our trunk tends to have a stabilizing function and our feet and legs a motor function, which is seen in advanced levels. The novice skier show otherwise: the trunk tends to be used as a motor unit and the legs as a balance function, hence the tendency to keep them rigid. This is why; to be efficient, we should generate the necessary forces from our base of support (feet and legs) to maintain a stable posture and adequate mobility.
Motor Planning
Each voluntary movement requires planning before being executed. This includes a visual image of the environment and an anticipated mental representation of the motor execution serving as a guide to our intentions. It also assists in our movements’ organization, identifying the involved body parts, and the spatial location where these movements will be oriented.
In summary, in movements’ execution, we will approach as close as possible to our action plan and to the image obtained from our internal representation, which is the motivating energy of executing those movements.
Motor Execution and Energy Consumption
Generally, during learning, adjusting our technical gesture is limited to the execution observation of one or more body parts, but not so much to energy production used to improve performance.
When learning to ski it is fundamental to improve movements, actions, and postures to reduce energy expenditure that muscle efforts produce. The acquisition of a motor habit and its relationship to energy expenditure would cover three consecutive phases.
- In the first phase, we perform our movements with insecurity and mixed efforts because of the lack of coordination, originating an energy waste while executing excessive movements (uncontrolled movements). We strive to approximate that execution to our mental representation of what the motor goal should be.
- In the second phase, we tend to pay more attention to motor control thereby reducing energy expenditure (controlled movements).
- In the third phase, automation initiates through movements’ dynamic stabilization. We activate specific nerve centers of the motor control which reflects a minimum necessary expenditure (automatic movements).
