Training Youth Populations:

Working with a diverse range of age groups and abilities is common for strength and conditioning professionals. When it comes to power training, it’s crucial to tailor training programs to suit populations with distinct characteristics. This section outlines power training guidelines for two such populations: young, developing athletes and older individuals who might have various medical factors to consider.

Youth Populations:

Power is a fundamental physical capacity for individuals of all ages, including children and adolescents. Whether young individuals are involved in sports, engage in recreational physical activity, or perform daily tasks, the ability to generate neuromuscular power is essential. Power is particularly crucial for dynamic sporting performance, as higher power outputs often correlate with superior athletic success. Muscular power is also important for activities that involve force absorption, such as rapidly changing direction or handling unexpected movements.

One common method for developing neuromuscular power in youth populations is resistance training. Resistance training encompasses various forms, including bodyweight exercises, weight machines, free weights (barbells and dumbbells), elastic bands, and medicine balls. Contrary to previous concerns about its safety, resistance training is now widely recognized as a safe and effective means of developing muscular strength and power in children and adolescents. It should be an integral part of their daily physical activity. Professionals designing and implementing athletic development programs for youth should possess a strong understanding of pediatric exercise science, recognized strength and conditioning qualifications (e.g., certified strength and conditioning specialist), pedagogical knowledge, and the ability to communicate effectively with youth of different ages and abilities.

Assessing Power in Youth Populations:

When assessing neuromuscular power in young individuals, various testing protocols and equipment are available. Common methods include jumping, sprinting, or projection tasks. These tests can involve the use of force plates, linear position transducers, mobile contact mats, motion analysis systems, and isokinetic dynamometry. For short-term power output, the Wingate anaerobic test using a cycle ergometer has been used.

When conducting these tests with youth, it’s crucial to provide familiarization sessions, clear, child-friendly instructions, and age-appropriate equipment. For assessing neuromuscular power or the effectiveness of training interventions, test protocols that involve single maximal efforts at submaximal velocities and loads are encouraged. The vertical jump is one of the most commonly used test protocols for assessing neuromuscular power in pediatric populations. Peak power can be calculated using force plate data or indirectly through jump height and body mass using contact mats. Vertical-jump protocols are frequently employed due to their ease of administration. They are used to track motor skill development in school-age youth, assess physical performance in young athletes, monitor training effectiveness, and are part of talent identification protocols in sports.

It’s important to understand that muscular power in children and adolescents increases nonlinearly due to growth and maturation. These natural developmental changes can sometimes be misconstrued as training-induced adaptations. Therefore, practitioners should consider the typical performance gains related to growth and maturation, as well as measurement errors associated with testing equipment, to accurately assess meaningful changes in performance due to training.

Natural Development of Neuromuscular Power in Youth:

The development of neuromuscular power in youth follows a trajectory similar to that of muscular strength, given the close relationship between these two physical qualities. Children between the ages of 5 and 10 years experience natural gains in neuromuscular power, largely attributed to the maturation of the central nervous system. This maturation enhances the activation and coordination of motor units and improves neural drive. Another significant spurt in neuromuscular power occurs about 18 months before peak height velocity, which typically happens around 10.5 years for girls and 12.5 years for boys. Peak height velocity represents the period of most rapid growth during adolescence. Adolescence is characterized by structural and architectural changes in contractile tissue, increases in hormone concentrations (e.g., testosterone, growth hormone, insulin-like growth factor), muscle size, muscle pennation angle, and motor unit differentiation.

Trainability of Neuromuscular Power in Youth:

Research indicates that traditional resistance training, ballistic exercises, plyometrics, and weightlifting are commonly used to develop neuromuscular power in youth. While there is limited research on the interplay between growth, maturation, and the trainability of neuromuscular power, several studies show that both children and adolescents can increase this physical quality through appropriate resistance-based training interventions. Traditional resistance training, plyometrics, weightlifting, explosive strength training, and combined training have all been found to be safe and effective in enhancing various aspects of neuromuscular power in youth.

It’s important to note that hypertrophic adaptations in children are limited, so gains in neuromuscular power during childhood are primarily driven by changes in the nervous system. In contrast, during adolescence, training-induced gains in neuromuscular power involve adaptations to the nervous system as well as structural and architectural properties. Muscular strength and neuromuscular power are closely related, and individuals with higher strength levels have a greater capacity to produce power. Thus, resistance training should be a fundamental component of youth-based strength and conditioning programs. Such programs should aim to develop sound movement mechanics while increasing muscular strength levels. By focusing on movement competency and muscular strength, practitioners can indirectly enhance neuromuscular power. Given the current trends of reduced muscular strength levels and motor fitness in modern-day youth, this approach is particularly valuable.

Research has demonstrated the effectiveness of resistance training in youth soccer players, with significant gains in strength and power as they age. Strength levels relative to body weight increased with age, indicating the importance of long-term, periodized resistance training for youth athletes. Notably, even children not involved in competitive sports have shown improvements in muscular strength and endurance, as well as neuromuscular power, through age-appropriate training programs. Such programs can lead to lasting benefits in strength, with neuromuscular power requiring more frequent stimuli to prevent detraining.

Plyometric training has also been found effective for improving stretch-shortening cycle (SSC) function in youth, although the response may vary by age. This suggests that younger children may require different training durations or that training-induced adaptations take longer to appear in younger individuals. Cumulatively, the studies confirm that children and adolescents can make gains in neuromuscular power through resistance training and show that neuromuscular power gains may diminish more rapidly than muscular strength in youth, underscoring the need for a long-term approach to training for athletic development.

Translating the Science Into Program Design:

When designing training programs for children or adolescents, it is essential to consider several key factors:

1. Technical Competency: Progression in training should primarily depend on the individual’s technical competency. This means that the ability to execute exercises correctly and safely is the primary factor determining the training program’s design.
2. Training Age: Training age refers to the relative experience a child or adolescent has with formalized training. Coaches should take into account the individual’s exposure to different types of training and their level of familiarity with various exercises and training modalities.
3. Biological Maturation: The biological maturation stage of the person should be considered, as different stages of development come with unique physiological adaptations that may affect the design of the training program.
4. Psychosocial Maturity: The psychosocial maturity of the individual should also be considered when designing a program. This factor takes into account the emotional and social development of the child or adolescent. For example, a child with lower confidence levels may require simpler exercises, more conservative progressions, and additional patience compared to a confident and extroverted adolescent.

Case Study 1 (Child With No Training Experience and Low Technical Competency):

When working with a young child who is new to formalized strength and conditioning programs and has low technical competency, it’s crucial to focus on building a foundation of motor skills that will improve overall athleticism. Rather than immediately targeting muscular power, the emphasis should be on increasing muscular strength levels. This approach allows the child to develop a solid and highly coordinated neuromuscular system, making them more resilient to reactive and unpredictable forces experienced in activities like sports and recreational play.

Children with low technical competency should also engage in various activities that promote the development of other fitness qualities, such as coordination, speed, power, agility, and flexibility. The heightened neural plasticity associated with childhood makes it an excellent time to train various neuromuscular qualities. Taking a holistic approach to athletic development is crucial for maintaining the interest and motivation of young children during training sessions. The use of child-friendly activities and games can effectively incorporate power training into training programs.

In terms of developing neuromuscular power, childhood serves as an opportunity to establish the foundation of athleticism, which can later support more advanced training as children gain experience and increase their technical competency. For instance, a fundamental goal for children with low technical competency might be to master effective jumping and landing techniques. Over time, as their technical competency and muscular strength improve, they can gradually introduce more advanced plyometric exercises that challenge them with greater eccentric stress.

Case Study 2 (Technically Competent Adolescent With 6 Years of Training Experience):

When an adolescent has engaged in formalized training during childhood and possesses good technical competency, adolescence is an ideal stage to build on their existing neuromuscular fitness. Developmentally appropriate training programs can be designed to complement the hormonal changes occurring during puberty, leading to enhanced neural, structural, and architectural adaptations.

In this phase, technically competent adolescents with a solid training history can work on generating more force at higher velocities, thus improving their capacity to produce high levels of neuromuscular power. Their training should incorporate a range of resistance training modalities using higher intensities, more advanced training strategies, or greater technical demands. Regular assessments of motor skill competency should be conducted to address any technical deficiencies resulting from growth spurts, muscle imbalances, or the risk of injury.

By tailoring training programs to the individual’s technical competency, training age, biological maturation, and psychosocial maturity, strength and conditioning coaches can effectively support children and adolescents in their athletic development. These considerations ensure that training programs are safe, effective, and engaging for young athletes at various stages of their development.

One Size Does Not Fit All: 

However, it’s crucial to acknowledge that this plan may not be suitable for an athlete who lacks adequate training experience and technical competency for advanced training strategies. In such cases, training prescriptions should still be based on the individual’s technical competency, but the coaching approach for teaching fundamental motor skills to older youth may vary compared to younger children.

It’s important to note that untrained adolescents, despite having greater muscular strength, may lack flexibility or have muscle imbalances that need addressing in the early stages of the program before focusing on the development of neuromuscular power. Conversely, naturally gifted and highly athletic children should be allowed to progress to more advanced training strategies and increased intensities, while still maintaining their technical competency. These scenarios emphasize the necessity for practitioners to adopt a flexible and individualized approach to training youth, considering their unique needs, experiences, and capabilities.

Training Older Adults:

Older adults, typically aged 65 and above, benefit significantly from the development of neuromuscular power. This is crucial for retaining neuromuscular function as they age and for preventing falls, which can lead to increased morbidity and mortality. Retaining neuromuscular function is essential for maintaining the ability to perform daily activities and preserving muscle mass, contributing to a healthy body composition and weight.

The decline in neuromuscular function with aging is well-documented. Several physiological changes occur as people age. These changes include muscular atrophy, a reduction in muscle mass, and the loss of faster-contracting Type II muscle fibers. This loss of muscle mass is often referred to as sarcopenia. With aging, motor neurons related to these muscle fibers also decline in function, leading to reduced force production and contraction speed. Additionally, connective tissue becomes less elastic and stiffer, impairing the transmission of force from muscle to tendon.

Strength and power gradually decline between the ages of 30 and 50, with the most significant decline occurring after the age of 60. Power tends to decline more rapidly than strength. Loss of power can be as high as 3% per year during this age range, leading to visible functional losses. Maintaining or improving neuromuscular power is essential for older adults to ensure they can maintain their independence and quality of life. Power training in older populations has been explored in various studies. Common power training modalities include hydraulic or pneumatic resistance exercise machines and free weights. Machine exercises are often preferred for novice lifters as they are less complex, restrict movements to one plane, and are generally safer. These exercises accommodate resistance and adjust to the lifter’s level of effort, increasing safety.

Despite the challenges posed by age-related neuromuscular declines, older adults can still benefit from power training. Strength remains a vital component for the development of power, and older individuals can successfully improve movement speed through a well-structured power training program. Power training for older adults can be approached in two ways: high-speed explosive movements and movements with the intent to move quickly. Each approach has its advantages and drawbacks. Explosive exercises can be more challenging due to higher forces and risk of injury. Pneumatic or hydraulic machine exercises allow for the intent to move fast without the ballistic characteristics at the end of the range of motion, but they may not mimic normal movements as effectively.

Assessing Power in Older Populations:

In the context of older populations, assessing neuromuscular power typically involves the use of various equipment and measurement devices. Common tools include force plates, linear-position transducers, pneumatic resistance machines, dynamometry, and accelerometry. These measurement devices can offer sensitivity to changes in power in older adults, especially when combined with electromyography (EMG). Given that changes in explosive power measures, such as vertical jump performance, tend to be smaller and take longer in older adults compared to younger individuals, field tests like vertical jumps may not be sensitive enough to detect subtle changes. However, for most older adults, the goal is to improve their performance in activities of daily living rather than training for specific events or competitions.

Translating the Science Into Program Design:

Designing resistance training programs for older adults, which incorporate power exercises or a power development phase, requires a thorough needs analysis. This analysis considers individual differences in training and medical histories, influencing exercise selection and the periodization of training. Importantly, older adults should receive medical clearance for exercise participation, and serious orthopedic or cardiorespiratory conditions, along with medications that may affect their physical exertion ability, should be considered.

A secondary concept in designing resistance training programs for older adults is the recovery time between sessions, which should generally be longer than for younger individuals, for example, 72 hours instead of 48 hours. Nevertheless, specific studies examining performance and adaptations after different recovery intervals in older adults remain limited.

Once an older adult’s assessment is completed and medical clearance obtained where needed, exercises can be selected. For power training, the most effective explosive exercises involve multiple joints and muscles, including machine and free-weight exercises like jump squats and leg-press throws. A critical aspect is to develop a strength base for these exercises before performing them in a ballistic or explosive manner. Since aging brings motor unit recruitment changes, older adults may require more time to learn and execute exercises correctly. As such, frequent exercise rotation may not be the best approach for novice lifters.

Incorporating these exercises into a periodized program is the next step, and this phase should be well-thought-out to match the primary training goal, whether it’s hypertrophy, strength, or power. For novice older lifters, a more singular focus on muscle development, followed by strength and then power development, is recommended. In contrast, more highly trained older adults may progress through different exercise styles more quickly within a particular phase. The challenge with older adults is determining how to load exercises effectively for power development. Studies have indicated that power can increase in older individuals with loads ranging from 20% to 80% of their maximum, and the choice of loads is influenced by exercise selection and training goals.