Updated: Aug 11, 2021
The purpose of training is to improve our performance capacity. This improvement is specific to the type of training we undergo. This is achieved as the body adapts to stress put on our body. If you want to improve your sprinting speed for example, training needs to be specific to increasing the stride length, stride rate, and the rate of force development. There are several ways this can be achieved, either directly (tangible) or indirectly (intangible). Direct adaptations are changes to the physiological structure. In contrast, indirect adaptations are often changes caused to the central nervous system, and improvement is more visible seen with skill performance.
When you squat with heavy resistance for example, your body will undergo physiological adaptations to perform this movement with those heavyweights by increasing muscle size (hypertrophy) leading to an increase in lower-body muscle strength which can generate larger ground reaction forces that are essential for sprinting. Plyometrics training can also help improve the rate of force development and helps strengthen the tendons so they are more elastic, both important components for sprinting. These adaptations are all direct adaptations. However, squats and plyometrics are also considered complex motor skills that need to be done correctly. They use multiple joint movements and if done incorrectly can cause injuries to the knees and lower back. Therefore, the skill itself needs to be learned and improved before going for heavier weights or more intense workouts. The learning of the skill is an example of indirect adaptations. Similarly, training the sprinting technique, even at low intensities, helps improve neuromuscular control, making the body more efficient during sprinting by recruiting more muscle fibers.
The General Adaptation Syndrome (GAS) helps us explain direct adaptations whilst the Fitness-Fatigue model helps explain indirect adaptations (for more info about these theories read the blog: adaptations to training). However, there are many instances where these models work simultaneously and can be interchanged with one another.
Many training programs focus on physiological adaptations since it is easier to monitor structural changes such as muscle growth or weight loss rather than measuring neuromuscular adaptations. However, both adaptations are essential for performance. If we take a marathon runner, training should focus on developing VO2 max, which is the maximum amount of oxygen that the body can use during exercise, which uses physiological structures such as the blood to carry oxygen, and the muscles that receive this oxygen to use for energy. However, by working on technique and neuromuscular adaptations, the athlete can become more efficient, so there will be no wasted movements and poor technique (improved running economy).
In recent years, the term movement training has become popular as well which focuses a lot on indirect adaptations and movement quality. A coach should focus on developing training programs that help improve both direct and indirect approaches. Neglecting one aspect of training can hinder performance development.
Thanks for reading, and as always stay fit!
Barnes, K. R., & Kilding, A. E. (2015). Strategies to improve running economy. Sports medicine, 45(1), 37-56.
Catina, P. (2000). Teaching proper technique in the squat exercise through psychological modeling. The Online Journal of Sport Psychology, 2(3), 4-5.
Ebben, W. P., Simenz, C., & Jensen, R. L. (2008). Evaluation of plyometric intensity using electromyography. The Journal of Strength & Conditioning Research, 22(3), 861-868.
Francesco, F., & Greco, G. (2017). Multilateral methods in Physical Education improve physical capacity and motor skills performance of the youth. Journal of Physical Education and Sport, 17(3), 2160-2168.
Pareja‐Blanco, F., Alcazar, J., Cornejo‐Daza, P. J., Sánchez‐Valdepeñas, J., Rodriguez‐Lopez, C., Hidalgo‐de Mora, J., ... & Ortega‐Becerra, M. (2020). Effects of velocity loss in the bench press exercise on strength gains, neuromuscular adaptations, and muscle hypertrophy. Scandinavian Journal of Medicine & Science in Sports, 30(11), 2154-2166.