Should pre-adolescent kids lift weights or shouldn’t they? Will it stunt their growth or increase their likelihood of future sporting success? Is growth plate damage a real concern or merely an exaggerated issue?

This debate has raged on for years.

Hopefully, this article will help clear up some of the concerns.

To start, there are definitive differences between adolescent boys and adolescent girls with respect to strength and strength production. In boys, absolute muscular strength (the greatest amount of force an individual can produce) grows consistently between the ages of 7 – 19. In girls, strength gains are incurred on a consistent level until about the age of 15, when a period of stagnation occurs and strength gains plateau, and in fact begins to fall. By the end of the pubescent ages, boys are roughly 50% stronger than girls.

There are several factors to consider when programming strength training for young athletes –

• Central Nervous System Maturity – The true argument with respect to children and weight lifting should not be based on the maturity (or in this case immaturity) of the child’s muscular system, but rather the advancement of the child’s CNS. Within proper application of load, volume and intensity, a child’s muscular system will not be compromised by weight training activities. However, a lack of motor control (a function of the CNS) will affect the child’s ability to perform weight-training exercises safely. It is therefore the maturity of the CNS that is the ultimate determining factor.

• Cross Section Of Muscle – A larger muscle infers a greater strength potential. While hypertrophy of this sort is not hormonally possible with pre-adolescent athletes, this fact is why I advocate that early adolescent athletes train with hypertrophy-based responses in mind.

• Biological Maturity – Biological age, unlike a child’s chronological age, is not actually visible. Biological age is based in large part to the “physiological development of the various organs and systems in the body” (Bompa, 2000). For example, the adequate development of bone, the efficiency of the heart and lungs to transport oxygen; these are examples of items that comprise biological age. This becomes important when determining the volume or intensity of the training program for the young athlete.

• Hormonal Issues – Androgenic (muscle building) hormones are low in pre-adolescent athletes. This means that hypertrophy-based responses are all but impossible. Strength gains, however, are very possible.

• Technical Issues – Providing a proper foundation of the technical merits of strength training is paramount when working with youngsters.

On the argument of effectiveness, adequately programmed strength training has shown considerable positive effects with regards to pre-adolescents. A study quoted by Dr. Drabik in his wonderful book, “Children & Sports Training” shows a 40% increase in strength for boys and girls (aged 10 – 11) following a nine-week strength-training program. In terms of danger or contraindication, the greatest concern lies in ligament or bone damage. Elastic, young skeletons and connective tissue can be injured if loads are excessive. That follows the mantra that with kids, loads must be kept low and proper form strictly followed.

Of interesting note is the argument regarding strength training and stunted growth. In the event of bone or growth plate damage (which is unlikely during strength training if the program is designed correctly), growth can in fact be stunted. But, if proper strength training parameters are prescribed, than the opposite is true. Muscle pull (which refers to the tension or ‘tugging’ where the muscle attaches to the bone and is incurred during muscle contraction), is a significant factor that stimulates bone thickness. More over, ‘intermittent use of submaximal resistance stimulates height growth’ (Drabik, 1996).

One keynote point that I have preached endlessly is the fact that an orthopedic assessment MUST precede any strength training prescription. Postural defects can be made worse by incorrect application of strength training and conversely improved by correct application. An assessment is a mandatory precursor to any child's strength training program.

Here is a list of exercises to do with young athletes -
(Dr. Drabik adopts thisl ist from "Children & Sports Training")

The exercises in this list get progressively more difficult. Start younger athletes on the earlier exercises, and progress them systematically over the years:

• Obstacle courses, rope pulling, climbing

• Vertical strength (standing push-ups), hanging exercises

• Bodyweight exercises and medicine ball based activities/throws

• Horizontal strength (push-ups, pull-ups)

• Dumbbell & barbell exercises

• Single leg squats, deadlifts, step-ups, good mornings

References:

"Children & Sports Training" by Jozef Drabik, 199