Foundations of Energy Systems Development

Related Topic: A Note on Fatigue and Acute Recovery

     Gymnastics submits athletes and their bodies to difficult training sessions and grueling competitive seasons that are physically and mentally demanding [2,4]. The push to quickly learn new skills means that the gymnasts are introducing very young bodies to drastic force demands at a quick rate and in high numbers--there is a stark difference in force and impact between basic skills and high-level skills [14] Muscular fatigue impairs performance, and gymnasts typically train in a fatigued state, often paired with caloric restriction [2]. Physical and mental fatigue and consequent loss of concentration can lead to mistakes in execution, which may lead to decreased scores or injury [2,4]. Loss of concentration and inattentiveness due to high levels of fatigue have been shown to be associated with gymnastics injuries, especially in children and adolescents [5]. Adequate rest and recovery are therefore essential to preventing fatigue and lapses in judgment [5,14]. In clubs training in excess of 20 hours per week, fatigue was a major factor contributing to injury [5]. Unfortunately, training 20 to 40 hours per week is the expectation for gymnasts aspiring to the elite levels of the sport. 

     A 2017 study by Buckner et al found that young gymnasts require 72 hours to fully recover--the standard 12 to 24 hours between gymnastics workouts is insufficient [4,11,13]. The authors recommended that coaches periodize training weeks to place easier workouts between harder workouts [4]. A periodized approach to strength and plyometric training programs was also recommended and proven effective in reducing injury risk and ensuring performance benefits [1,4,7,11,12,13]. By following the recommendations that weekly practices be periodized to include light days and rest days, with hourly rest periods including during daily sessions, injury risk due to fatigue may be reduced [5,14] Additionally, long practices on a single apparatus contributed to lapses in concentration that resulted in injury [5].

Metabolic and Energy Systems Considerations

     Gymnastics is a multifaceted sport with a variety of metabolic performance requirements. The competitive events range in length from a few seconds (vault) to approximately 90 seconds (floor) and require a combination of the many performance characteristics discussed throughout the materials on this website [5]. Research estimates that 80-90% of the energy required for gymnastics performance is obtained from anaerobic sources, with minimal energy coming from aerobic pathways [5]. 

     Proper energy systems development directly impacts gymnastics performance. Gymnasts who are not properly conditioned may struggle to execute routines and may suffer from errors, large form breaks or falls that may lead to injuries, and lower scores [14]. Unfortunately, energy systems or metabolic conditioning is another area in which there are gaps between research and current application in the sport of gymnastics [14]. There is a lack of understanding of the energy systems, metabolic physiology, and fueling as they relate to the demands of the sport, leading to confusion on prescribing training or “conditioning.” Too often, this misunderstanding leads to inappropriate training prescription and subsequent frustration when gymnasts are not adapting as expected [14]. In order to achieve the highest levels of performance and ensure safety during training, it is imperative that coaches understand the basics of the energy systems, as well as the parameters surrounding the prescription of work to rest ratios, and periodization of energy systems training. 

Foundational Concepts:

     There are 3 main energy systems in the human body--the ATP/PC pathway, anaerobic system, and aerobic systems. Contrary to popular belief, the 3 energy systems do not function independently of one another. In reality, these systems are all turned on at the beginning of exercise or activity, but contribute in different amounts depending on the activity at hand. Gymnastics relies heavily on the ATP/PC pathway for vault and very short burst efforts (single tumbling passes on floor, for example). Anaerobic glycolysis accounts for the majority of competitive gymnastics routines on the uneven bars, balance beam, and floor exercise [8]. This makes ATP/PC and anaerobic glycolysis the most important energy systems to target for competitive performance.  That said, the event practices required to prepare for competition consist of more than just one or two quick turns--these longer practices will rely more heavily on the aerobic system for recovery of the important substrates needed to produce quick energy (and therefore perform powerful high-level gymnastics skills and routines). Thus, appropriately training the aerobic system in this manner increases recovery capacity, allowing gymnasts to safely take more high quality turns during practices. It may help coaches to think of energy systems development in terms of work capacity, or how much a gymnast can accomplish without seeing declines in performance, whether in training or at the end of a difficult floor routine.  

Review of Current Training Practices and Issues

     Gymnastics is a sport that requires high-intensity exercise endurance (HIEE). The longest competitive event in women’s artistic gymnastics is floor exercise, which has a time limit of 90 seconds. The shortest event is vault, which requires one or two attempts lasting between 4-7 seconds. Uneven bars and balance beam fall within a range of 30-75 seconds, typically (slightly higher at the elite levels). All of these events rely primarily on an anaerobic energy supply. However, low-intensity exercise endurance (LIEE) training--such as jogging-- is very popular with many gymnastics coaches. The development of LIEE in primarily anaerobic sports can result in maladaptations that can reduce the athlete’s performance capacity [3]. Observed maladaptations include reduced power-generating capacity due to reduced ability to produce force in the high-velocity region of the force-velocity curve, limiting the athlete’s ability to develop explosive strength [3].  LIEE reduces the athlete’s ability to achieve high rates of force development and generate high levels of peak force, likely due to a decrease in type II fibers and an increase in type I fibers as an adaptation to LIEE training [3]. Generally, LIEE training should not be used for athletes in predominantly anaerobic sports requiring high levels of force production, high rates of force development, fast velocities of movement, or require high levels of power output [3]. Gymnastics certainly checks these boxes.  

     Gymnastics requires high power outputs and the repetitive performance of high-velocity movements in the execution of skills and routines. HIEE is defined as the ability to sustain and repeat high-intensity exercise that preferentially activate the anaerobic energy systems [3]. HIEE training tends to maintain type II muscle fiber content, which is instrumental to the maximal rate of force development, maximal force-generating capacity, and the ability to generate peak power outputs [3]. LIEE methods substantially decrease rate of force development and peak force generation ability, which depend on the energy system activated, the muscle fiber type, and neuromuscular recruitment patterns [3]. Conversely, the ability to generate force rapidly is an important foundational element of HIEE [3].

     HIEE training also has the potential to improve LIEE [3]. HIEE training induces an increase in concentration or activity of key enzymes in the phosphagen and glycolytic energy systems, as well as increases in muscular stores of ATP, phosphocreatine, and muscle glycogen [3]. These adaptations allow for more rapid energy supply during high-intensity bouts of exercise, thus the athlete can maintain a higher level of performance [3]. Gymnasts also need the ability to buffer lactic acid (H+ ions) to lactate in order to maintain power output during practice and performance [3]. This ability must be achieved in training--training must stimulate the production of H+ ions, necessitating activities in which the fast glycolytic system is repetitively called upon [3]. HIEE training increases VO2max, stroke volume, and the ability to use oxidative metabolism during recovery from interval training, all of which are imperative for recovery from repetitive bouts of high-intensity exercise [3]. Oxidative metabolism is imperative for recovery, as replenishment of phosphocreatine and lactate removal are aerobic processes [3]. 

     High-intensity interval training (HIIT) allows for improvements in anaerobic power, anaerobic capacity, and aerobic power [3]. Interval training typically consists of repeated sprints interspersed with recovery intervals [3], however other high-intensity activities that mimic the needs of the sport may also be implemented in the work intervals. Work to rest ratios, interval intensities, interval duration, interval exercise volume, training duration, frequency, progression, and resistance training can all be manipulated based on sports needs and training phase of the annual plan [3]. 

     Work to rest intervals should match the needs of the sport [3]. In the absence of detailed evidence on appropriate work to rest intervals for gymnastics, research for similar sports can be perused to determine the most appropriate range, and intelligent “trial and error” can be implemented by the coach to determine the exact range. Each competitive event has slightly different needs. Floor exercise, for example, consists of a moderate-high intensity level of activity for 90 seconds interspersed with 3-5 tumbling passes and/or high-level dance passages at an all-out intensity. These higher intensity passes last between 3-5 seconds each, and are somewhat evenly spaced throughout the entire floor routine. This information provides a good base for determining appropriate intervals. Interval training frequency is best limited to 1 to 2 days per week due to the increased risk of overtraining [3]. My girls have an interval training day on their final practice day of the week, allowing for a few days of complete rest before the next practice/training session. As core endurance is also a major component of gymnastics performance and injury prevention[6], this training day is shared with a localized core muscular endurance program matching the work to rest intervals of competitive routines on various events. As the competitive season approaches, these training sessions become more competition interval specific and shift from multilateral (general) exercise selection to more specific exercise selection. Likewise, the volume should decrease as intensity increases nearing the competitive season [3]. This shift, along with incorporating conditioning into sports practice during training (skill sets and routine work in careful volumes) will allow for the development of specific endurance.

     

     Strength training also improves HIEE, likely due to increases in muscular strength, morphological adaptations, or metabolic adaptations that increase buffering capacity [3]. Including resistance training with repetitions of 12 or more per set or more than eight repetitions for multiple sets and higher volumes most improves HIEE [3]. This is one way that resistance training program design can improve work capacity for gymnastics routines and performances.

 

     The six endurance training intensity zones can be arranged in order from the highest power output (zone 1) to the lowest power output (zone 6) [3]. The zones most relevant to gymnastics are 1, 2, 4, and 6. Zone 1 (Alactic System Training or the ATP/PC System) is most relevant for vault and tumbling on floor, which use short sprints to generate power for a high-level gymnastics skill to follow. These activities rely mainly on the phosphate energy system and require long recovery periods. Zone 2 (Lactic Acid Training or LAT) represents the majority of the competitive routines gymnasts perform. Training in this zone increases an athlete’s ability to perform during lactic efforts and tolerate lactic acid buildup [3]. Developing a gymnast’s ability to clear lactic acid from the blood by transporting it to slow-twitch muscle fibers for energy usage is a fatigue-delaying adaptation that will especially improve performance in the floor exercise and uneven bars events [3]. Zone 4 (Anaerobic Threshold Training or AnTT) is an intensity at which the rate of lactic acid diffusion in the bloodstream equals the rate of its removal [3]. Lactic acid produced in muscles diffuses into adjacent resting muscles, lowering concentration in the working muscles [3]. Zone 6 (Aerobic Compensation Training or CoT) facilitates athlete recovery from high-intensity training or competition [3]. Light intensity workouts eliminate metabolites from the system to speed recovery and regeneration and should be planned to follow workouts or competitions that include activities in Zones 2 or 3. 

 

     The following table gives some basic guidelines for energy systems development throughout the training year, following the suggestions of Ramsbottom [13].

References

  1. Agostini, B. R., Palomares, E. M. D. G., Andrade, R. D. A., Uchôa, F. N. M., & Alves, N. (2017). Analysis of the influence of plyometric training in improving the performance of athletes in rhythmic gymnastics. Motricidade, 13(2), 71-80.

  2. Batatinha, H. A. P., da Costa, C. E., de França, E., Dias, I. R., Ladeira, A. P. X., Rodrigues, B., & Caperuto, É. C. (2013). Carbohydrate use and reduction in number of balance beam falls: implications for mental and physical fatigue. Journal of the International Society of Sports Nutrition, 10(1), 32.

  3. Bompa, T & Buzichelli, C. (2019). Periodization: Theory and Methodology of Training. Champaign, IL: Human Kinetics.

  4. Buckner, S. B., Bacon, N. T., & Bishop, P. A. (2017). Recovery in level 7–10 women’s USA artistic gymnastics. International Journal of Exercise Science, 10(5), 734.

  5. Daly, R. M., Bass, S. L., & Finch, C. F. (2001). Balancing the risk of injury to gymnasts: how effective are the countermeasures?. British Journal of Sports Medicine, 35(1), 8-19. 

  6. Durall, C. J., Udermann, B. E., Johansen, D. R., Gibson, B., Reineke, D. M., & Reuteman, P. (2009). The effects of preseason trunk muscle training on low-back pain occurrence in women collegiate gymnasts. The Journal of Strength and Conditioning Research, 23(1), 86-92.

  7. French, D. N., Gómez, A. L., Volek, J. S., Rubin, M. R., Ratamess, N. A., Sharman, M. J., Gotshalk, L…. & Hakkinen, K. (2004). Longitudinal tracking of muscular power changes of NCAA Division I collegiate women gymnasts. The Journal of Strength & Conditioning Research, 18(1), 101-107. 

  8. Gateva, M. (2014). Investigation of the effect of the training load on the athletes in rhythmic and aesthetic group gymnastics during the preparation period. Research in Kinesiology, 4(1), 40-44. 

  9. Haff, G. G., & Triplett, N. T. (Eds.). (2015). Essentials of strength training and conditioning 4th edition. Human kinetics. 

  10. Lloyd, R. S., & Oliver, J. L. (Eds.). (2019). Strength and conditioning for young athletes: science and application. Routledge. 

  11. Michel, M., Monèm, J., & Ferran, R. (2014). A two-season longitudinal follow-up study of jumps with added weights and countermovement jumps in well-trained pre-pubertal female gymnasts. Journal of Sports Medicine and Physical Fitness, 54(6), 730-741. 

  12. Ramírez-Campillo, R., Andrade, D. C., & Izquierdo, M. (2013). Effects of plyometric training volume and training surface on explosive strength. The Journal of Strength and Conditioning Research, 27(10), 2714-2722. 

  13. Ramsbottom, H. Strength and conditioning for gymnastics.. https://gymbc.org/public/uploads/Strength-and-Conditioning-Manual-2020.pdf

  14. Tilley, D. (2018). Changing Gymnastics Culture: Reflections, Lessons, and Visions for the Future (1st ed.). Retrieved from https://shiftmovementscience.com/freeresourcelibrary/