Taastumine pärast jõutreeningut — sportlane puhkab jõusaalis

Recovery in strength training: processes and factors

Recovery after strength training is much more than simply resting. It is a complex biological process in which your body restores its energy stores, repairs muscle damage and triggers the adaptations that make you stronger for your next workout (Ivy 2004). Without proper recovery, muscles don’t grow — training provides the stimulus, and recovery finishes the job.

Recovery starts during the workout itself

Many people think recovery begins after the workout. In fact, it kicks in between sets — this is known as immediate recovery. Oxygen returns to the muscles, creatine phosphate stores are replenished (the creatine phosphate system covers energy demand for roughly 3–15 seconds) and the pH balance is corrected. The glycolytic system can supply the muscles with energy for 60–120 seconds, but in doing so it produces lactate and hydrogen ions, which lower pH. During the recovery period, lactate in the blood and muscles is broken down and H⁺ is removed by buffer systems such as HCO₃ (Wilmore, Costill 1994).

Long-term recovery means recovery between workouts. This is where most muscle growth and bodily adaptation takes place.

Recovery at the cellular level: energy, hormones and muscle fibers

Strength training depletes the creatine phosphate and ATP stores in your muscles. During recovery, these stores are rebuilt and the glycogen supply is replenished as well. The body stores glycogen in the muscles and liver; intense training largely empties these stores. After training, the body synthesizes new glycogen from blood sugar — which is exactly why carbohydrates are an important component of post-workout nutrition (Wilmore, Costill 1994).

Training causes micro-damage in skeletal muscles. This triggers hypertrophy: protein synthesis increases and new muscle fibers form (Coffey, Hawley 2007). Muscle growth doesn’t happen during the workout — it happens afterward, during recovery. The calcium pump in the muscle cell needs ATP; when the pump is depleted, muscle contractility is impaired. During the recovery period, this system is recharged (Wilmore, Costill 1994).

Hormonal changes are critical too. Strength training sets catabolic processes in motion — muscle tissue is broken down during the workout — but during recovery, anabolic hormones dominate, driving growth and repair (Kraemer & Ratamess 2005).

Recovery: what affects it?

People recover differently. Why? Here are the main factors.

The nature of the workout. The greater the training load and the more muscles involved, the longer the recovery period. Particularly heavy eccentric exercises can require up to 72 hours of recovery; moderate training loads often recover faster (Kraemer & Ratamess 2004).

Training experience. Less-trained people need longer to recover. In a study in which untrained women of different ages performed a lower-body workout — 5 sets of 10 repetitions with a 10RM weight —, they regained on average about 94% of their strength within just two rest days (Kraemer & Ratamess 2004).

Genetics and age. Muscle fiber composition is largely determined by genetics and changes little over a lifetime. The proportion of fast-twitch fibers declines with age, which directly affects recovery capacity (Wilmore, Costill 1994).

Sex. Some measures — heart rate, arterial blood pressure, body temperature — respond similarly in men and women during and after training. In other measures, however, there are clear differences: in men, systolic blood pressure, blood plasma shifts, the pulmonary ventilation ratio and blood lactate concentration increased more (Deschenes et al. 2006).

Nutrition, sleep and rest. Nutrition is a key factor in recovery — it supports rehydration and the replenishment of energy stores. When the time between workouts is short, nutrition becomes especially critical (Décombaz 2003). Sleep, relaxation, emotional support and active rest influence recovery just as much (Kenttä, Hassmén 1998).

FAQ

How long does recovery take after a heavy strength training session?
It depends on the training load and the exercise regimen. Particularly heavy eccentric loads can require up to 72 hours; moderate and high training loads often recover within 24–48 hours.

Is recovery different for men and women?
Partly. Heart rate and body temperature respond similarly, but blood plasma shifts and lactate levels rise more in men after training (Deschenes et al. 2006).

What speeds up recovery the most?
Three things in combination: suitable nutrition after training (carbohydrates and protein), enough sleep and planned rest days. Supplements can support recovery, but they don’t replace these three factors (Décombaz 2003, Thomas et al. 2007).

References:

Braith, R.W; Beck, D.T (2008). Resistance exercise: training adaptations and developing a safe exercise prescription. Heart Fail Review. 13:69–79
Coffey, V.G; Hawley, J.A (2007). The molecular bases of training adaptation. Sports Med. 37(9): 737-763
Décombaz, J (2003). Nutrition and recovery of muscle energy stores after exercise. Sportmedizin und Sporttraumatologie. 51(1): 31–38
Deschenes, M.R; Hillard, M.N; Wilson, J.A; Dubina, M.I; Eason, M.K (2006). Effects of gender on physiological responses during submaximal exercise and recovery. Medicine & Science in sports & exercise. 38: 1304-1310
Ivy, J.L (2004). Regulation of muscle glycogen repletion, muscle protein synthesis and repair following exercise. Journal of Sports Science and Medicine. 3: 131-138
Kraemer, W.J; Ratamess, N.A (2005). Hormonal responses and adaptations to resistance exercise and training. Sports Med. 35(4): 339-361
Kraemer, W.J; Ratamess, N.A (2004). Fundamentals of Resistance Training: Progression and Exercise Prescription. Medicine & Science in sports & exercise. 36(4): 674-688
Mike, J.N; Kravitz, L (2009). Recovery in training: the essential ingredient. IDEA Fitness Journal. 6(2): 19-21
Thomas, C; Perrey, S; Saad, H.B; Delage, M; Dupuy, A.M; Cristol, J.P; Mercier, J (2007). Effects of a supplementation during exercise and recovery. Sports Med. 28: 703–712
Wilmore, J.H; Costill, D.L (1994). Physiology of sport and exercise (Chapter 2;3;4;5;6;7;15;18). Human Kinetics