Five Categories of Motor Skill and Athletic Training Development

According to Dr. Ivan Bayli, Dr. Richard Way, and Dr. Colin Higgs,  motor skill and athletic development can be broken down into five categories: Stamina, Strength, Speed, Skill, and Flexibility. These categories are always trainable, but improve at a greater pace if the proper workouts are applied during the right periods of development.  These periods are referred to as optimal windows of trainability. By training during the sensitivity period, strength and aerobic development can reach higher potentials than would be achieved by training according to chronological age. Your chronological age is your age in years, while your biological age is your age in relation to developmental landmarks such as your growth spurt and other developmental events. Coaches can take advantage of sensitive training periods by monitoring the rate at which an athlete is growing, and training in the proper developmental windows to optimize results.

PHV: Peak Height Velocity (greatest change in height)


The amount of oxygen a person can consume while exercising increases naturally during age 8 – 15 by 150% in boys, and 80% in girls.  The period when a person is the most sensitive for training is at the onset of the growth spurt. Boys show an increase in lung capacity after their greatest increase in height (Peak Height Velocity; PHV). This window usually lasts from around age 16 – 18. Female lung capacity development peaks around age 14, with smaller, steady increases until age 16. Bayli’s research found that beginning one year prior to the PHV and continuing training thereafter, lung capacity was effectively increased above the norm attributed to age and growth.


At the start of the growth spurt, sports that require a lot of stamina should prioritize lung capacity during continuous training with long, slow, distance exercises.  Once the growth spurt decelerates, training should be focused on aerobic power: the highest amount of oxygen a person can consume during maximum exercise over the course of several minutes. Increasing aerobic power takes two types of training: increasing muscle strength and stamina so they use oxygen more efficiently, and increasing your cardiovascular strength to deliver more oxygen to your muscles.

VO2 Max: Lung Capacity


Children are able to produce strength gains before the growth spurt, but only in regards to relativity to their body weight, not absolute strength. This means as children grow, their strength increases at the same rate at which they grow until they reach their growth spurt. In females, the optimal window of trainability begins at the onset of menarche. In males, it is 12 to 18 months after the growth spurt.


Athletes that are going to engage in strength training should be taught proper weightlifting form before PHV to get maximum results during the window of optimal trainability. Olympic lifting techniques and free weight exercises can be introduced at that time.

Optimal windows of strength trainability in females starts PHV and at menarche.

The window of optimal strength trainability in males is 12 – 18 months after PHV.


There are two optimal windows for speed trainability. In females, they are from around age 6 – 8, then age 11 – 13. In males, the windows are from age 7 – 9, and age 13 – 16. The first window coincides with the development of the central nervous system. This makes it a sensitive period to train agility and change of direction because of the muscular control and reaction development necessary to be agile.


During the first sensitivity period, agility training should be low volume and high intensity: less than five seconds in duration with a full recovery between sets. Speed training should start only in the second sensitivity period. There are two components to speed training: Anaerobic alactic power, and anaerobic alactic capacity. Think of anaerobic alactic power as your top speed, and anaerobic alactic capacity as the duration you can perform at top speed. The anaerobic alactic energy system is responsible for providing short, massive bursts of energy.  Training during the second sensitivity period should be sets of 5 – 20 seconds, with a full rest between sets.

Speed training should be done at every training session. The best time to train speed is toward the end of the warm-up or immediately after it because of the lack of central nervous system or metabolic fatigue. When training speed, you should always keep the volume low, and have a full recovery between sets. To maximize effectiveness, accelerations should be done over a short distance with a focus on proper posture and position.


Skill is most trainable between the ages of 5 and 12, with peak motor skill development occurring between age 8 -11 for females, and 9 – 11 for males. Although skills are always trainable, skill trainability greatly declines after age 12. Fundamental skills should be acquired before age 11 for girls and 12 for boys. Some examples of fundamental skills are agility, balance, coordination, jumping, throwing, catching, and kicking, among others.  If the skill development  foundation isn’t properly developed early, it could lead to trouble with skill development later in life.


Early sport-specific training can lead to a lack of broader skill development, and hinder future athletic ability. That’s why it is important to have balanced fundamental skill set development, which can be achieved by participating in a wide variety of sports at a young age.


The sensitivity period for flexibility occurs before the growth spurt (usually age 9 – 12).


Information on how to best develop flexibility is limited, but a good place to start is the warm-up before a training session. Dynamic (moving) stretches should be done before every training session. Static (stationary) stretches should be limited to 2 hours before or 2 hours after a workout.