The benefits of strength and conditioning (S&C) training for athletes of all levels have been long established. Athletes who engage in well-structured and evidence-based off-season S&C programs can make significant gains in strength, power and other performance measures, as well as reduce their risk of injury (1,2). The reality is that most athletes, especially those in competitive team sport, spend the majority of the calendar year in a competitive phase. This means that without an effective in-season S&C approach, athletes risk decreasing a large portion of the performance gains they made in the prior off-season (3).

In-season training presents a unique challenge to athletes, sport coaches, and S&C specialists because the volume of S&C training has to be balanced proportionately with an athlete’s competitive and practice schedule. This presents a potential roadblock as coaches and parents (of youth athletes) may often not see the benefit in sacrificing sport practice time for time spent in a S&C setting. There is often a misconception or unclear information portraying that participation in additional S&C work while in-season may result in overtraining, injury, or skill loss. Additionally, new strength coaches who have never programmed for athletes in-season may struggle with the necessary changes to their approach that are necessary during this time. Even experienced coaches have admitted that in-season S&C training presents an area of discomfort (4).

Thus, the purpose of this article is to provide education on the benefits of participating in structured in-season S&C programming. Additionally, this article outlines how flexible undulating periodization may be the most beneficial approach to in-season S&C.

The Value of In-Season Training

Despite the current dilemma of in-season training, the benefits of taking part in S&C during this phase have been demonstrated in both practical settings and exercise science literature. In-season S&C training has been shown to help maintain performance gains made in the off-season, contribute to injury resistance, enhance recovery, manage fatigue, and reduce athlete burnout by exposing them to different physiological stimuli (2,5,6).

By participating in an effective in-season S&C training program, athletes can ensure that the physiological advances made in the previous off-season are not negatively impacted. Additionally, it is possible that athletes can improve some performance markers during their competitive season such as: vertical jump, lower body power, total body power and estimated VO₂ max (2). If athletes choose not to participate in in-season S&C training, they risk starting from lower baselines once their competitive season has concluded, thus decreasing their chances of reaching their full potential.

One example at the professional level of in-season S&C training involves the 2017 New England Patriots. During the week leading into the Super Bowl, athletes were squatting up to 80% of their 1 repetition maximum in training as stated by the Patriots wide receiver Matthew Slater. The Patriots went on to win the Super Bowl after overcoming a 25-point deficit (7). While participating with in-season S&C was certainly not the sole reason for the Patriots success, it was likely a contributing factor.

Increased injury resistance and recovery are other key benefits of in-season S&C training. Athletes who engage in structured S&C work are less likely to miss time due to injury and are less likely to suffer severe injury when compared to those who opt out of taking part in in-season S&C training (1,6). Furthermore, athletes who are healthy have higher availability to attend planned training and will often achieve greater sports success (8). Additionally, S&C training has the ability to enhance musculoskeletal recovery and reduce cumulative fatigue over a long competitive season (9). This has implications for injury resistance and performance capacity. Athletes who can recover more efficiently and perform at higher levels of performance will make more valuable contributions for a longer period of time. This fact is important as it goes against the general misconception that in-season training can negatively impact recovery and injury risk.

Finally, utilizing S&C training in an athlete’s in-season practice schedule has implications for psychological factors such as athlete burnout (6). By allowing athletes to engage in physical activity in a context outside of their sport of choice, they have increased chances to learn and grow, which has implications for lifelong engagement with physical activity (6). While this may not be of high concern in professional, high-performance athletes, it is certainly applicable for youth athletes. By incorporating in-season S&C training, athletes may become more satisfied with their sport experience in the long term.

Recommendations

Given the current concerns and misconceptions surrounding in-season S&C training, it is imperative that programs designed for this period utilize the best practices and evidence available. S&C professionals must continue to engage with current research and collaborate with professionals to continue to offer athletes the greatest chance of success by designing effective in- season S&C training protocols. Recognizing this fact, utilizing flexible non-linear (undulating) periodization may be the most efficient way to structure in-season S&C programming. This approach to exercise program design allows for more flexibility and can be adjusted based on athlete needs and other individual factors such as fatigue or stress. Non-linear periodization also involves greater focus on the variables of intensity and volume, which are more frequently changed (10,11). According to Fleck (2011), non-linear periodization is just as good of an approach, if not a better one, for programs that focus on the variable of athlete strength compared to traditional models (12). This variable is a cornerstone of in-season programs, and thus this model appears to be a promising approach. See Figure 1 for an example of an in-season training schedule for a youth hockey athlete.

Additionally, a study on collegiate soccer players conducted by Silvestre and colleagues (2006) found that using a flexible method of non-linear periodization did maintain or increase performance markers throughout a season (2). This study is especially meaningful because it suggests that athletes can improve while training in-season. Commonly, in-season strength training is programmed so that the primary goal is to maintain progress earned during the off-season. Maintaining is good as far as it goes, but why not strive for performance enhancement continuously? If athletes can improve without compromising competitive efforts, then this is what we should aim for. In pursuit of this improvement, however, it is important that we keep exercise selection general, limit variations and heavy frequent eccentrics in order to keep the athlete’s body primed and ready to perform. Introducing these can heavily tax the individual’s central nervous system and muscular tissue, which could compromise performance in a competitive setting. While improvement is an important goal to consider, we must not be overzealous in our pursuit of this outcome.

As current understandings of, and perspectives on, in-season training are sometimes unclear and or contradictory, it is important to set a clear path to facilitate buy-in from athletes, players, coaches, and parents where applicable. In our opinion, athletes cannot become their best selves and perform to their maximum ability without participating in S&C training during their competitive season. It is now up to S&C professionals and exercise science researchers to continue investigating this subject to further the development of athletes at all ages and competitive levels.  Particularly, aiming to establish best practices such that athletes can continue to improve in-season without overtraining or overreaching. Additionally, it would be valuable for researchers to investigate the perspectives athletes and coaches hold regarding engaging with S&C training while in season.

Co-Author Bio: Jon Reid is a former high performance athlete. He was fortunate to have the opportunity to play Major Junior and University hockey. Following his hockey career, Jon went on to complete a Bachelor Degree in Physical Education and a Master Degree in Science of Kinesiology at Memorial University in Newfoundland and Labrador. Jon is a certified Kinesiologist with the Newfoundland and Labrador Kinesiology Association. Jon is currently the Director of Exercise Science at APSolute Performance and Wellness, located in Paradise Newfoundland as well as a Strength and Conditioning Coach with the Newfoundland Growlers of the East Coast Hockey League.

Co-Author Bio: Tristan Dower-Nichols is a 4^th year Bachelor of Kinesiology student at Memorial University of Newfoundland and Labrador. He is currently a Strength & Conditioning Coach at APSolute Performance & Wellness, as well as the Strength & Conditioning and Rehabilitation Assistant with the Newfoundland Growlers of the ECHL. Growing up around sport Tristan developed a passion for S&C training, and has been actively pursuing a way to blend this personal interest with his academic and professional pursuits. Along with his current Strength and Conditioning work, Tristan is leading a research project exploring sport coaches’ perspectives on S&C training. These are balanced with his participation in competitive powerlifting, as he is slated to compete at the CPU National Championships in May 2022.

References

1. Fleck, S. J., Falkel, J. E. (1986). Value of resistance training for the reduction of sports injuries. Sports Medicine, 3, 61-68. https://doi.org/10.2165/00007256-198603010-0000
2. Silvestre, R., Kraemer, W. J., West, C., Judelson, D. A., Spiering, B. A., Vingren, J. L., Hatfield, D. L., Anderson, J. M., Maresh, C. M. (2006). Body composition and physical performance during a national collegiate athletic association division I men’s soccer season. Journal of Strength and Conditioning Research, 20(4), 962-970. https://doi.org/10.1519/R-18165.1
3. Hakkinen. Changes in physical fitness profile in female volleyball players during the competitive season. J Sports Med Phys Fitness 33: 223-232, 1993.
4. Hedrick, A., Wiley, S., Bennett, S., & Rodgers, R. (2005). Learning from each other: In-season training. Strength and Conditioning Journal, 27(4), 75-78. https://doi.org/10.1519/00126548-200508000-00013
5. Nuckols, G. (2014, April 15). Daily undulating periodization: the boogeyman of training programs. Stronger by Science. https://www.strongerbyscience.com/daily-undulating-periodization/
6. Zwolski, C., Quatman-Yates, C., & Paterno, M. V. (2017). Resistance training in youth: Laying the foundation for injury prevention and physical literacy. Sports Health: A Multidisciplinary Approach, 9(5), 436-443. https://doi.org/10.1177%2F1941738117704153
7. Schrotenboer, B (2017, Feb 6). Bill Belichick didn’t flinch in Super Bowl comeback, and the Patriots followed his lead. USA Today
8. Raysmith, B., Drew, M. (2015). Performance success or failure is influenced by weeks lost to injury and illness in elite Australian track and field athletes: A 5-year prospective study. J Sci Med Sport 19(10) 778-783.
9. Smith, C. W. [Juggernaut Training Systems]. (2017, July 3). Undulating Periodization Strategies [Video]. YouTube. https://www.youtube.com/watch?v=LbmCDI_EHKY
10. Fleck, S. J., Kraemer W. J. (2004). Designing resistance training programs (3rd ed.). Human Kinetics Publishing.
11. Kraemer, W. J., Fleck, S. J. (2007). Optimizing strength training designing non-linear periodization workouts. Human Kinetics Publishing.
12. Fleck, S. J. (2011). Non-linear periodization for general fitness & athletes. Journal of Human Kinetics, Special Issue, 41-45. http://dx.doi.org/10.2478/v10078-011-0057-2

Additional Resource:

Gill, M. (2018, March 16^th). Why Every Athlete Needs In-Season Strength Training (and How to Do It Right). Stack. https://www.stack.com/a/why-every-athlete-needs-in-season-strength-training-and-how-to-do-it-right/