Detraining effect in footballers

With the FIFA World Cup 2014 around the corner, the national players are still in training and competition mode and all players will compete in at least three games (however, everyone is hoping for seven.

However, this post is not about these players, its about the other players that are not present in the World Cup, enjoy their vacation and most likely do not train (at all, or at least have reduced their training).  The question here arise how the players react to a reduced training load or no training load at all? Of course I do not necessarily meant to talk about the injured players.

In the scientific literature, the partial or complete loss of training-induced adaptation, in response to an insufficient training stimulus (17 - see references below) is called detraining (and here it seems obvious that injuries can also be seen as a kind of detraining as well). Detraining is a common phenomenon in sports (basketball (3) and the term “use it or loose it” seems to be proven right.

Before I would like to go into detail about the different detraining possibilities, I would like to highlight the general “football performance detraining”. Obviously performance in football is a construct consisting of different components, which is the reason why simple and easy to measure (football) performances such as a single sprint are mentioned in this section, even though it is not a “real” football performance. Furthermore, and due to the fact that there is not a lot of knowledge in a football background, I looked for other team sports (such as field hockey, then basketball, handball and other football codes), then for individual sports involving running and finally some clinical studies.

Sprint and agility
3 weeks of detraining showed significant decrease in 50-meter spring time in professional Serbian footballers (19). 8 weeks of between season rest was enough to significantly lower 15-meters sprint performance and Illinois agility test in semiprofessional English footballers (4).

Jump
Countermovement jump height was reduced after 2 weeks in physical educational students (11) and more importantly after 8 weeks of detraining in semiprofessional English footballers (4).

Strength
Experienced resistance trained adults (high-level football code athletes, mostly rugby and American football) showed an average decrease of 14.5% (±14.3) in strength after a detraining period of 7.2 weeks (±5.8). The authors suggested that the adults were able to maintain the majority of their pre-season strength levels with no resistance training over a detraining period of 2-3 weeks (15). Other researchers suggested that elite athletes may be able to maintain maximum strength gains for up to 4 weeks (6, 10, 18).

However, highly trained athletes' eccentric force and sport-specific power, and recently acquired isokinetic strength, may decline significantly (18).

Youth athletes seemed to “loose” strength gains slower. 8 weeks of non-training resulted in a significant loss of upper (-19%) and lower body (28%) strength in children(8). Furthermore, 8 weeks again was enough to loose resistance strength gains even though a maintenance program was performed 1/week  in 9-11 year old boys (14).

Flexibility
The sit-and-reach test was utilized to investigate the lower back and hamstring muscle group for flexibility. Detraining after 8 weeks negatively affected flexibility in semiprofessional football players (4).

Anthropometry
Body fat was significantly increased after 3 (19), 4 (12) and 8 weeks (4) of detraining in semi- (4) and professional (12) footballers. Generally, the highest %body fat was reported for pre-season values (coming from off-season) (16).

Additionally, a significant decrease in adductor muscle were also observed after 4 weeks (12).

Other
Upper and lower body strength/power gains (after 12 weeks) were reduced after 12 weeks of detraining in pre- and early pubertal boys (13).

Hip rotation range of motion decreased as an effect of football training and a stretching was shown to partially benefit the hip range of motion of Brazilian youth footballers (7).

Additional thoughts
Interestingly, reduced training and detraining (4-16 weeks) of upper- and lower-body explosive strength in adolescent basketball players was not enough to loose strength gains after a 10-week in-season complex training. It seems that the regular basketball training was able to preserve the players upper- and lower-body strength (21). As a consequence, it could be plausible that football might have the same effect.

Physiological detraining
Maximal oxygen consumption was reduced significantly after 8 weeks of detraining in semiprofessional footballers (4).

Interestingly, 3 weeks of detraining followed by 4 weeks of training was sufficient to keep the level of VO2max of Danish National football players (2).

Significant changes in the anaerobic threshold for different parts of the season (pre – mid – end) were observed in professional soccer players (5). Pre-season values were the lowest, followed by end-of-season and mid-season revealing the highest data over all three years. However, no differences in VO2max were observed suggests the preference of the anaerobic threshold over VO2max in monitoring.

Increases in phosphorfructokinase after training for 3 month were abolished in the 6 month detraining in adolescent boys (9). However, 7 weeks to 6 month is needed in adults to return to baseline enzyme activity (20) in adults.

Physical detraining
The summer break (4-8 weeks) was invested in youth amateur Spanish footballers. Muscle biopsies were taken and the results showed an decreasing effect on cross-sectional area of type 1 and 2 muscle muscle fibers and important enzymes for aerobic and anaerobic endurance (1).

Furthermore, it seems that detraining appears to shift the contractile characteristics towards type IIb , although muscle atrophy is also likely to occur (20) in adults.

Due to the low amount of literature, it is impossible to draw definite conclusions. It seems that (and from my experience) 2 weeks of absence from training will not affect the player’s performance (at all). Indeed it seems necessary (especially at the end of the season) to have a rest period, not only for psychological reasons. A detraining period of up to 4 weeks might not affect the players too much, however, peak performance (in all its facets) might be impossible to reproduce up to pre-detraining standards. Longer periods (probably >4 weeks) of absence of appropriate stimuli will significantly decrease players performance.

Detraining in youth might be dependent on their training status and their specific trainability to a given stimulus.

Unfortunately, it seems that there is a lack of literature on technical and tactical detraining (and possibly even psychological detraining – if that exists).

References

1. Amigo N, Cadefau JA, Ferrer I, Tarrados N, Cusso R. Effect of summer intermission on skeletal muscle

of adolescent soccer players. J. Sports. Med. Phys. Fitness. 38(4): 298-304, 1998.

2. Bangsbo J, Mizuno J, Morphological and metabolic alterations in soccer players with detraining  and

retraining and their relation to performance, in Science and Football, T. Reilly, et al., Editors. 1988, E. & F. Spon: London.

3. Bogdanis GC, Ziagos V, Anastasiadis M, Maridaki M. Effects of two different short-term training

programs on the physical and technical abilities of adolescent basketball players. J Sci Med Sport. 10(2): 79-88, 2007.

4. Caldwell BP, Peters DM. Seasonal variation in physiological fitness of a semiprofessional soccer team.

J. Strength. Cond. Res. 23(5): 1370-1377, 2009.

5. Clark NA, Edwards AM, Morton RH, Butterly R. Season-to-season variations of physiological fitness

within a squad of professional male soccer players. J. Sci. Med. Sport. 7: 157-165, 2008.

6. Cormie P, McGuigan MR, Newton RU. Developing maximal neuromuscular power: part 2 - training

considerations for improving maximal power production. Sports. Med. 41(2): 125-46, 2011.

7. de Castro JV, Machado KC, Scaramussa K, Gomes JL. Incidence of decreased hip range of motion in

youth soccer players and response to a stretching program: a randomized clinical trial. Journal of Sport Rehabilitation. 22(2): 100-107, 2013.

8. Faigenbaum AD, Westcott WL, Micheli LJ, et al. The effects of strength training and detraining on

children. J. Strength. Cond. Res. 10(2): 109-114, 1996.

9. Fournier M, Ricci J, Taylor AW, Ferguson RJ, Montpetit RR, Chatiman BR. Skeletal muscle adaption in

adolescent bays: sprint and endurance training and detraining. Medicine and Science in Sports & Exercise. 14(6): 453-456, 1982.

10. Hakkinen K. Neuromuscular adaptation during strength training, aging, detraining and immobilization.

Phys Rehab Med. 6(3): 161-198, 1994.

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plyometrics and strength training with and without superimposed electrical stimulation on muscle strength and anaerobic performance: A randomized controlled trial. Part II. J. Strength. Cond. Res. 24(6): 1616-1622, 2010.

12. Hoshikawa Y, Kanno A, Ikoma T, et al. Off-season and pre-season changes in total and regional body

composition in Japanese professional soccer league players. J. Sports Sci. 22(6): 546, 2004.

13. Ingle L, Sleap M, Tolfrey K. The effect of a complex training and detraining programme on selected

strength and power variables in early pubertal boys. J. Sports. Sci. 24(9): 987-997, 2006.

14. Malina RM. Weight training in youth-growth, maturation, and safety: an evidence-based review. Clin J

Sport Med. 16(6): 478-487, 2006.

15. McMaster DT, Gill N, Cronin J, McGuigan M. The development, retention and decay rates of strength

and power in elite rugby union, rugby league and American football: a systematic review. Sports. Med. 43(5): 367-384, 2013.

16. Morgan N, Weston M, Nevill A. Seasonal variation in body composition of professional male soccer

players. J. Sports Sci. 23: 1209, 2005.

17. Mujika I, Padilla S. Detraining: loss of training-induced physiological and performance adaptations. Part

I: short term insufficient training stimulus. Sports. Med. 30(2): 79-87, 2000.

18. Mujika I, Padilla S. Muscular characteristics of detraining in humans. Med Sci Sports Exerc. 33(8):

1297-303, 2001.

19. Ostojic SM. Seasonal alterations in body composition and sprint performance of elite soccer players.

Journal of Exercise Physiology online. 6(3): 24-27, 2003.

20. Ross A, Leveritt M. Long-term metabolic and skeletal muscle adaptations to short-sprint training:

implications for sprint training and tapering. Sports. Med. 31(15): 1063-1082, 2001.

21. Santos EJ, Janeira MA. Effects of reduced training and detraining on upper and lower body explosive

strength in adolescent male basketball players. J Strength Cond Res. 23(6): 1737-1744, 2009.