Post-exercise turmeric: a fast-track route for match recovery?

Rapid recovery is an integral and essential part of any training program. All other things being equal, an athlete who recovers faster will be able to train more frequently and harder than an athlete with slower recovery, which in turn will result in greater fitness gains and better performance.

As all athletes know (or should know!), enhancing recovery from training or racing sessions entails ensuring adequate rest and nutritional replenishment, including fluid for rehydration, carbohydrate for restoring muscle glycogen, and protein for the repair and regeneration of damaged muscle tissue. However, more recent research suggests that some naturally occurring antioxidant compounds found in certain plants may also have much to offer.

Muscle damage and recovery

Assuming nutrition is optimized and muscles are refueled, why do muscle structures themselves require a recovery period following hard or long bouts of exercise? The reason is that muscle fibers are not perfectly resilient, so when placed under load, some damage to the muscle fibers can and does occur. In addition, muscle tissues also experience a degree of ‘oxidative damage’, where energetic by products of oxygen metabolism interact and damage muscle cells⁽¹⁾. This oxidative damage however is part and parcel of normal metabolism, and may even help to stimulate training adaptation⁽²⁾.

However, this damage can be seen as a normal and healthy response to training; during the recovery period after training, any damaged tissue is broken down and removed, then replaced with new and healthy tissue. This post-exercise muscle damage is now widely understood to be the main cause of the muscle soreness that occurs after particularly strenuous workouts, or those containing unfamiliar movement patterns⁽³⁾.

Signs and symptoms of exercise-induced muscle damage (EIMD) generally appear shortly after exercise (within 24-36 hours) and often persist for several days, sometimes as long as up to 14 days after exercising^(4,5). This is a real hurdle for athlete recovery because EIMD has a direct impact on athletes’ functional and exercise capacity. In addition to the muscle soreness, athletes typically experience a disturbed sense of force production and limb position, decreased pressure pain threshold (PPT) and elevated levels of muscle enzymes associated with micro damage and inflammation (such as creatine kinase, C-reactive protein, lactate dehydrogenase and myoglobin⁽⁶⁾.

Combating muscle damage

As stated above, the focus of many sports nutrition strategies is to maximize the recovery from each exercise bout and prepare for the next exercise burst. Because muscle damage occurs partly as a result of oxidative damage, numerous nutrients and functional foods have been examined for their potential to decrease oxidative stress and therefore EIMD. In particular, naturally-occurring antioxidant phytochemicals (often brightly colored compounds found in plants such as polyphenols) have attracted the interest of scientists. This is because these types of compounds possess powerful antioxidant and anti-inflammatory properties, and may therefore reduce the impact of oxidative stress and inflammation markers, thereby lower the amount of EIMD following exercise, and enabling an earlier return to normal levels of muscle strength and force production in athletes⁽⁷⁾.

 A spicy approach

One of the potential anti-inflammatory, joint-health agents currently under intense scientific scrutiny is turmeric – or more specifically curcumin. Curcumin is derived from turmeric, which is a popular spice used in India, South Asia, and Japan. Turmeric is the ground root and root system of the plant Curcuma longa (see figure 1), and in traditional Indian medicine, turmeric is used to treat digestive disorders, wounds, and rheumatic diseases. Besides other macro and micronutrients, the extract of turmeric contains 77% curcumin, 17% demethoxycurcumin, and 3% bisdemethoxycurcumin, collectively named curcuminoids, which render turmeric its distinct orangey-yellowish hue (Figure 1). Curcumin is both a powerful anti-inflammatory and antioxidant, and such is the potency of this compound that isolated curcumin extract has anti-inflammatory properties similar to that of non-steroidal anti-inflammatories such as Ibuprofen and aspirin⁽⁸⁾. 

Figure 1: Cumcuma longa root