Youth Performing Resistance Training: A Review

Transcription

1 Youth Performing Resistance Training: A Review Lance Peltier Shanley High School Brad Strand North Dakota State University Bryan Christensen North Dakota State University Resistance training for adults has been growing in popularity for years (Sporting Good Manufacturers Association, n.d.); but more recently, prepubescents and adolescents have also become increasingly more active in this fitness activity. In years past, youth resistance training was frowned upon because it was thought to be completely unsafe and ineffective. Presently, resistance training is accepted as an effective component of youth fitness programs (Faigenbaum & Schräm, 2004; Faigenbaum, Kraemer, Cahill, Chandler, Dziados, et al. 1996). Several professional organizations have adopted position statements supporting youth resistance training. The National Strength and Conditioning Association (NSCA) is widely recognized as one of the foremost leaders in resistance training. Their current position statement on youth completing resistance training states that they believe that it is safe, effective, enhances motor skills, prevents injuries, improves psychosocial well-being, and can enhance the overall health of children (NSCA, n.d.) Within this paper, the term youth is defined as the period of life that includes both the prepubescent and adolescent years. In addition, resistance training is defined as a specialized form of conditioning that is used to increase one's ability to exert or resist force (Faigenbaum, Kraemer et al,, 1996). This is not to be confused with power lifting or competitive weight lifting. The purpose of this paper is to provide a review of the literature regarding four aspects of youth resistance training. It begins with a discussion on the value of youth resistance training. This is followed with a discussion of the risks and concerns with youth resistance training. Next, we discuss the psychological effects of resistance training on youth and conclude with a section on training program designs and testing. Value of Youth Resistance Training In the past 20 years, scientific research has confirmed that resistance training will increase the strength of youth as long as a program is followed consistently and safely (Blimkie, 1992; DeRenne, Hetzler, Buxton, & Ho, 1996; Faigenbaum, Westcott, Loud, & Long, 1999; Faigenbaum, Westcott, Michell, et al,, 1996; Faigenbaum, Zaichowsky, Westcott, Micheli, & Fehlandt, 1993; Fálk & Mor, 1996; Guy & Micheli, 2001 ; Isaacs, Pohlman, & Craig, 1994; Pfeiffer & Francis, 1986; Ramsay, Blimkie, Smith, Gamer, MacDougall, et al. 1990; Sailors & Berg, 1987; Siegal, Camaione, & Manfredi, 1989; Westcott, 1979). As a child develops, he or she goes through dramatic physiological changes. Muscular strength, defined as the maximal force a muscle or muscle group can generate, will normally increase from childhood into the early teenage years. At that time, strength accelerates markedly in males and plateaus in females (Faigenbaum, Westcott, et al., 1996). Because the bodies of youth are going through strength gains as a natural function of growth and development, it is difficult to carry out valid research in a short amount of time when testing strength gains in youth. Consequently, it is evident that extended periods of time are needed to accurately liieasure strength gains in youth engaged in resistance training programs. It has been suggested that with an effective, safe, and valid resistance training study, over longer periods of time, that children can show improvements in strength over what is typically seen in strength gains by developing youths (DeOliveria & Gallagher, 1995), More current literature using higher training volumes and longer training periods confirm that resistance training can stimulate strength gains beyond what is generally the effect of maturation and growth (Falk & Tenenbaum, 1996; Guy & Michelli, 2001), Improvements in various anatomical and physiological measures have been noted in children who have participated in appropriately designed and well-supervised strength, training programs (Faigenbaum & Zaichkowsky^ 1997). Falk and Mor (1996) reported that children as young as 6, 7, and 8 years old engaged in martial arts and resistance training can benefit with strength gains and increased athletic ability. In addition to the increase in muscle endurance and strength, youth engaged in resistance training obtain the value added benefits of increased athletic ability and better all around health. Resistance training has been shown to strengthen bone, facilitate weight control, enhance self-esteem, increase bone mineral density, and improve one's cardiovascular-risk profile (Faigenbaum, 2002; Faigenbaum & Bradley, 1998; Naughton, Farpour-Lambert, Carlson, Bradney, & Van Praagh, 2000), The increased bone density that results from resistance training during youth can certainly help prevent the onset of osteoporosis later in life. Resistance training has been shown to benefit young athletes by preventing sport related injuries in sport performance (Faigenbaum & Schräm, 2004; Smith, Andrish, & Michelli, 1993) and to decrease injury rates in youth who performed structured resistance training programs before their sport seasons (Heidt, Swettman, Carlonas, Traub, & Tekulve, 2000; Hewett, Lindenfeld, Riccobene, & Noyes, 1999), If greater attention was 18 Peltier, Strand, & Christensen The Journal of Youth Sports Volume 4, Issue 1, 2008

2 given towards proper training programs and techniques, personal physical shortfalls, and psychological health, almost half of all injuries occurring in youth athletes could be prevented (Smith et al, 1993). It is difficult to prove that resistance training improves athletic ability, mainly beeause of the varying components related to athletic ability (Kraemer, Fry, Frykman, Conroy, & Hoffman, 1989). Christou and his eolleagues used groups of 12 to 15 year old male soccer players to compare a typical soccer training program to the same program with resistance training added (Christou, Smilios, Sotiropoulos, Volaklis, Pilianidis, et al. 2006). Although the group that performed the additional resistance training was found to perform 2.8% better on the soccer technique test, it was not found to be statistically significant. To date, there have not been any long-term research studies that measure preseason resistance training and youth sport performance. Conclusions as to the relation between a youth resistance training program and an inerease in sport performance are mixed, but it seems reasonable to suggest that an increase in strength will bring an increase in athletic performance because of the power and speed that comes along with an increase in strength (Faigenbaum, Kraemer et al., 1996). Obviously, if youth are stronger and more powerñil, one might assume that they will have an advantage over their opponents Some youth have seen gains in motor fitness skills (increased distances in the long jump and vertical jump) following resistance training programs (Falk & Mor, 1996; Weltman et al., 1986). Others, however, did not notice any increase in motor fitness skills after several weeks of resistance training (Faigenbaum et al., 1993). This may be expected since it is difficult to differentiate an increase in motor fitness skills related to a resistance training program and natural growth and development. Risks and Concerns With Youth Resistance Training For many years, one concern with youth performing resistance training was the belief that training could result in damage to the epiphyseal plate (growth plate) of the long bones. The epiphyseal plate is comprised of cartilage, which is much weaker than bone, thus making it vulnerable to pressure exerted upon it (Bright, Bumstein, & Elmore, 1974). Case reports have doeumented the fracture of an epiphyseal plate related to youth resistance training (Ryan &Salccioli, 1976; Brady, Cahill, & Bodner, 1982). However, most of these injuries were due to improper lifting techniques, maximal lifts, or lack of qualified adult supervision (Faigenbaum, Kraemer, et al., 1996). More recent studies have indicated that under competent supervision and controlled settings, there is no evidence of injuries to the epiphyseal plate due to youth performing resistance training (Faigenbaum, Milliken, & Westcott, 2003; Sadres, Eliakim, Constantini, Lidor, & Falk, 2001). According to the National Electronic Injury Surveillance System (NEISS), the most frequent resistance training related injuries in adolescents were reports of strains and sprains. However, the NEISS also documented lumbosacral injuries and epiphyseal plate fractures (Risser, Risser, & Preston, 1990). Many of the documented injuries "were actually caused by poor training, excessive loading, poorly designed equipment, free access to the equipment, or lack of qualified adult supervision" (Faigenbaum, Kraemer et al. 1996, p. 63). The NEISS data from 2004 shows that the majority of injuries to youth ages 10 to 17 during resistance training were caused by accidents such as walking into, pinching, or dropping weights as compared to nonaccidental injuries such as sprain, stains, and fractures (Meyer & Wall, 2006). Although extremely rare, resistance training accidents can be fatal (George, Stakiw, & Wright, 1989). However, it is unfair to relay the message that resistance training is unsafe for youths, provided they are given the proper guidance and instruction. The risk of repetitive-use soft tissue injuries may be the largest worry for youth engaged in resistance training programs. A survey of youth power lifters found that 50% of the 98 reported injuries were to the lower lumbar region, 18% to the upper body, 17% to the lower body, and 14% to the mid-section (Brown & Kimball, 1983). It was not completely known why the injuries occurred; however, it was theorized that maximal or near-maximal lifts were completed, including the possibility of inadequate exercise programs, leading to a high frequency of lower back injuries. Nonetheless, the potential f^or injury to the lower back should remain a concern for anyone working with youth engaged in resistance training programs (Faigenbaum, 2002). Anyone who performs resistanee training, including adults and youth, has a chance of being injured. However, most people who participate in sports and who have not engaged in resistance training, have a better chance of being injured while playing than someone who is performing resistance training. Zaricznyj, Shattuck, Mast, Robertson and D'elia (1980) evaluated the incidence of sports related injuries in school-aged children over a one-year period. Resistance training resulted in 0.7% of the 1,576 reported injuries whereas football, basketball, and soccer resulted in approximately 19%, 15%, and 2%, of all injuries, respectively. In fact, resistance training can significantly decrease the chances of youth getting injured while competing in athletics. A study of male and female high school athletes found that the injury rate for athletes who had not engaged in resistance training was 72%, while for those athletes who had been involved in resistance training programs, the rate was 26% (Hejna, Rosenberg, Buturusis, & Krieger, 1982). It was also found that the athletes who had been involved in resistance training programs recovered from their injuries in less than half The Journal of Youth Sports Volume 4, Issue 1, 2008 Peltier, Strand. & Christensen 19

3 the time compared to the athletes who had not been doing resistance training. Psychological Effects of Resistance Training on Youth Although often overlooked, the psychological effect resulting from resistance training is a major component of the learning experience in a fitness program. Resistance training should be taught in a manner that is enjoyable to the youth (Faigenbaum, Kraemer et al., 1996). Training should be similar to that found in a team sport, where teammates need to work together towards a common goal in order to achieve success. Enjoyment of resistance training may promote other healthy lifestyles, such as cardiovascular exercise, nutrition, and lifetime sports (Faigenbaum, 2003). For this reason, it is imperative that youth have competent adult supervisors who value the importance of a healthy lifestyle, make sure all training is done safely, and know how to make exercise fun. Youth who are involved in physical fitness programs have higher self concepts than youth who are inactive (Faigenbaum, 1995; Zaiehowsky, Zaiehowsky, & Martinek, 1975). Furthermore, youth who perform regular aerobic exercise have increased self-esteem, creativity, internal locus of control, and cognitive functioning (Faigenbaum & Zaichkowsky, 1997; Sibley & Etnier, 2003; Welsh & Labbe, 1994). Even though these findings occurred with youth performing aerobic exercise, it is hypothesized that the same may hold true for youth in resistance training programs (Faigenbaum, Kraemer, et al., 1996). Training Program Designs and Testing Youth resistance training should be exciting and challenging. Most importantly, youth should be taught safety measures along with proper form and technique while performing exercises. Table 1 provides basie guidelines and precautions for resistance training (Strand, Scantling & Johnson, 1996). Table 1 Guidelines and Precautions for Resistance Training All workouts should begin with a warm-up that consists of light stretching and aerobic activity. Begin your resistance training with one or more light warm-up sets for each exercise Keep the weight as close to the body as possible. The farther out from the body a weight in held, the more strain on the back When picking up a weight from the ground, keep the back straight, the head level or up, and lift with the legs. Bending at the waist with straight legs strains the lower back muscles and spinal discs of the lower back. Do not twist the body while lifting. Twisting places an uneven load on back muscles, causing strain. Lift the weight smoothly, not with throwing, bouncing, jerking, rapid motion. Sudden motions place more stress on the spinal muscles and discs. When training on a weight machine, make sure it is properly adjusted to the body. Uncomfortable, twisted positions may place unnecessary stress on vulnerable spinal muscles and nerves. Perform exereises through a full range of motion. When introducing a new exercise or beginning again after a lay-off of two or more weeks, ajways perform the movement with light weights. Never ignore pain in or around the joints. "No pain, no gain":is bad advice and can lead to chronic injuiy. Approach a onej-repetition maximum attempt with the utmost caution. Several weeks of training '\ together with proper instruction should precede any 1-RM attempt. Utilize a variety of exercises and work all body areas to promote joint stability and balance within the muscles of a body group as well as those of opposing groups. All workouts begin with the largest muscle groups and proceed down to the smallest. Training is done to build strength, not to demonstrate it. Do not hold your breath during strength activities. Use spotters in any exercise in which you can conceivably lose control of the weight. Do not use more weight than you are capable of handling safely and in good form and always use collars on barbells and dumbells. Follow lifting withi a sufficient stretching period. When developing a plan of overload, it is essential that youth have an adequate base of strength before increasing demand (Faigenbaum & Chu, 2001). There are three main types of resistanee training methods including, body weight exercises, machines, and free weights. All three methods of resistance training have their pros and cons (Myer & Wall, 2006). For many youth, simply using their body weight or resistance from a partner will provide enough resistance when starting a resistance training program. For example. 20 Peltier, Strand, & Christensen The Journal of Youth Sports Volume 4, Issue

4 push-ups and body weight squats may be diffieult for many youth. These types of body weight exereises ean involve deereased or inereased resistance by manipulating the position of the body and using bands or spotters. For example, eompleting push-ups from the knees to deerease the resistanee or elevating the feet to increase the resistanee (Fleek & Kraemer, 2004). Resistanee training machine and free weight exercises can be added as the youth develops increased strength. When using machines it is important that the youth is in the eorreet position to eomplete the exereise properly. Most exereise machines are designed for adults, therefore, youth may not fit in the maehines properly. If the machine cannot be adjusted to the proper position, pads may be added to put the youth in the correct position (Fleek & Kraemer, 2004). When using free weight exercises proper form should be used to avoid possible injury. Maximal force production testing using one repetition maximum (lrm) with resistanee training programs is rare with youth because most teaehers, trainers, eoaehes, and researchers do not want to risk personal harm. Nevertheless, there are studies that have shown that with proper warm-ups, teehnique, and supervision, maximal force production (lrm testing) ean be measured safely (DeRenne et al., 1996; Faigenbaum, Milliken, et al. 2003; Ramsay et al., 1990). However, in order to error on the side of safety, strength evaluations with youth are usually completed using a high-repetition maximum (Faigenbaum et al., 1993). For example, testing strength by having the youth complete the most weight they can for a 6RM or greater. A machine chest press and leg press can be used as tests of upper and lower body strength. There is a lack of normative data to eompare the results (Faigenbaum, Milliken, et al., 2003). However, the results of the strength testing can be used as a basis of how much resistance the youth should use at the beginning of a program, goal setting, and evaluating progress. Youth beginning resistance training programs should train 2-3 nonconseeutive days per week with one to three sets of 6-15 repetitions (Faigenbaum et al., 1996). The number of sets and amount of resistance used should be based on the youth's ability, experience, and individual improvement; not eompetition between the youth (Baechle & Earle, 2000). Progression of the resistanee training program is just as neeessary for continued gains in youth as it is for adults. The resistance training programs of youth ean progress by adding more resistanee, sets, reps, number of exereises, and more eomplex exercises. However, eare must be taken to not progress too fast and inerease volume so much that the youth looses their enthusiasm for resistance training. Qualified instruetors must always be present during workout programs to ensure that proper safety measures, along with faculty rules and regulations, are followed. In addition to lowering the chances of injury, youth have been found to inerease The Journal of Youth Sports Volume 4, Issue 1, 2008 strength more when they are supervised and are more likely to eontinue resistanee training in the future (Coutts, Murphy, Daseombe, 2004) The advantages that youth gain from partieipation in resistanee training programs can be quickly lost during periods of no training (Blimkie, 1993). The loss of benefits is due to the natural growth proeess. After a 20-week progressive resistance training program, a once-weekly maintenanee training program was not enough to maintain the training induced strength gains in prepubescent boys (Faigenbaum, Westeott, et al., 1996). However, DeRenne et. al, (1996) reported that a 1 day-a-week maintenance resistance training program was just as effective as a 2 day-a-week program following a 12 week resistance training program for pubescent boys. Maintenanee resistance training programs ean be low volume and therefore, less time consuming, whieh is valuable when training in season and time is limited. These maintenanee programs prevent the loss of the gains aehieved from the resistanee training program. Conclusion For far too long, many individuals in the fitness community have believed that growth of youth would be stunted if they performed resistance training. However, current researeh has shown that resistanee training does not slow down or affect development (Faigenbaum et al., 1993; Ramsay et al., 1990; Sadres et al., 2001; Sailors & Berg, 1987; Siegal et al., 1989; Weltmanetal., 1986). Youth should be active everyday and involved in three or more sessions weekly of moderate to vigorous physieal exertion for a period of 20 or more minutes (Sallis & Patriek, 1994). Youth and parents can feel assured that a proper resistanee training program ean be a component of an active lifestyle. Resistanee training programs designed for youth, that are properly supervised and are age-speeific, will result in similar health benefits that adults receive from resistance training (Faigenbaum, Kraemer, et al., 1996). In addition, it has been shown that youth do increase their self-effieaey when they perform resistanee training (Faigenbaum & Zaichkowsky, 1997). In eonclusion, youth resistanee training has shown to be very advantageous beeause it can increase muscle strength, muscle endurance, bone density, sports performanee, and much more (Faigenbaum, 2003). As an effeetive eomponent of a youth fitness program, resistance training ean effeetively grow along with a developing child. 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