Training Reversibility - Use it or Lose it !

We hear a lot about recovery after exercise, but what happens when we take a long break from training?  How much down time should we have off? When will detraining start to occur? ​ The principle of Detraining states that its the partial or complete reversal of exercise induced physical adaptations. This occurs when training is completely stopped or drastically reduced (Mujika,2000). Example.. take a highly active gym goer training 5 times per week, if they stopped training for a long period of time their hard earned fitness gains will begin to deteriorate. There is a fair amount of academic research around detraining for trained and untrained lifters based around muscular strength, endurance and muscle mass.

Muscular strength  (McMaster et.al. 2013) looked at the effects of detraining on muscular strength, it was stated that muscular strength levels can be maintained for up to 3 weeks without any resistance training however after 5 weeks’ deterioration will occur much quicker, another study that also supported this specified ‘Strength performance in general is readily retained for up to 4 weeks of inactivity, but highly trained athletes’ eccentric force and sport specific power may suffer significant declines. Beginners to resistance training differ slightly as Muscular strength is lowered after 3 weeks of detraining (Ogasawara, et.al. 2012)

Muscle mass Muscle atrophy is the term used to describe muscle wastage, it is defined as the decrease in muscle size due to inactivity, injury or disease. (Hortobagyi, et.al. 1993) study looked at loss of muscle mass within trained powerlifters, results show that type 2 muscle fibers decreased in size by 6% after a 2-week period of no training, however there wasn’t a change in muscle mass. There isn’t an exact cut off point when muscle atrophy begins to occur however individuals with injuries such as limb immobilization muscle mass is found to decline quicker compared to the individual who is just taking a break from the gym. When training for beginners its suggested that muscle atrophy occurs within 2 weeks (Hortobagyi, et.al. 1993). Although another study found that no difference occurred until 3-6 weeks suggesting its dependent on the individual, factors like nutrition, genetics and daily life will vary (Ochi et.al.2018). Sometimes between 2-3 weeks’ muscles may appear smaller in size this is because muscle water stores and glycogen within the muscle cells are decreased, but when training is started again these will rapidly regain their glycogen stores and increase in cross sectional area (Ribeiro, Avelar, Schoenfeld et, al. 2014)

Muscular Endurance During a break from exercise VO2max reduces quickly, in trained athletes it may decline from 6 - 20% after 4 weeks of inactivity (Mujika, Padilla, 2000). Overall endurance performance percentage decrease is 4 - 25% after 3-4 weeks of no exercise. Breaks longer than 2-3 weeks of cardiovascular activity should be avoided as the result is a lot worse compared to muscular strength (Bosquet, Mujika, 2012).

As the academic evidence suggests both trained and beginners can maintain muscle mass, strength and endurance for at minimum 2-4 weeks with little training. However, after 4 weeks or more significant decreases will occur. But when returning to training the physical adaptations to exercise can quickly be improved.

References Bosquet, Mujika, 2012, Detraining, Endurance training: science and practice, pp.100-106 Hortobagyi, Houmard, Stevenson et.al. 1993, The effects of detraining on power athletes, Journal of Medical Science Sports exercise,Volume 25, Issue 8, pp.929-35 McMaster, Gill, Cronin, McGuigan, 2013, The development, retention and decay rates of strength and power in elite rugby union, Rugby league and American football: a systematic review, Sports Medicine, Volume 43, Issue 5, pp.367-84 Mujika, Padilla, 2000, Detraining: Loss of Training-Induced Physiological and Performance Adaptation. Part 1, Sports Medicine, Volume 30, issue 2, PP.79-87 Ochi, Mauro, Tsuchiya et.al. 2018, Higher Training Frequency is important of gaining Muscular Strength Under Volume- Matched Training, Front. Physiology,9:744 Ogasawara, Yasuda, Ishii, Abe, 2012, Comparison of muscle hypertrophy following 6-month continuous and periodic strength training. European journal of applied physiology, Volume 113 Ribeiro, Avelar, Schoenfeld et, al. 2014, Resistance training promotes increase in intracellular hydration in men and women, European Journal of Sports Science,volume 14, Issue 6, pp.578-585