Curcumin is widely used and well recognized as a highly valued component of the turmeric root. Used extensively in India for cooking and medicinal purposes, it boasts many health promoting chemicals and has been the subject of intense research over the last few years for a variety of health benefits.1 The health promoting properties of curcumin have been further investigated to determine how they affect exercise performance. Curcumin is not only a potent antioxidant that helps to protect cells when they are under stress, but it also has the ability to protect and strengthen the cardiovascular system and to boost exercise performance, specifically by improving endothelial function and improving muscle recovery time.2,3

What Happens to the Body During Intense Exercise

Exercise can provide several health benefits to the body, but it can also cause stress to the cells comprising muscle and other tissues. The muscles that allow one to move, and the muscle tissue that allows the heart to pump blood through the body are all vulnerable to damage from various sources, one being exercise. However, we also know that exercise is vital for these tissues in order to strengthen them and to allow them to continue to perform their intended functions. Therefore, regular cardiovascular exercise is important and beneficial overall.

As the heart rate increases during exercise, the level of oxygen in the blood is improved and natural painkillers called endorphins are increased in the body. However, if the body is pushed into cardiovascular exercise for too long a duration it can enter into a catabolic state in which tissues start to break down; excess stress hormone (cortisol) is produced which contributes to this catabolic process of tissue breakdown. Microscopic tears can occur in the muscle fibers making healing a slower process if overtraining is continued. The risk of injury is also increased when overtraining occurs.4 In terms of the heart, studies on marathon runners show that the right ventricle of the heart is more susceptible to damage when overexertion occurs. Overtraining leaves the immune system in a weakened state and taxes the body’s organs. So the question might be asked, what can be done to protect the body’s cells and tissues during exercise? Supporting the body with antioxidants such as curcumin is known to have several benefits for protecting against the damaging aspects of exercise. Numerous research studies have investigated the various beneficial effects of curcumin in relation to physical exercise.

Improving Vascular Endothelial Function with Curcumin

Vascular endothelial function, which refers to the functioning of the inner lining of the blood vessels, declines with age and is associated with an increased risk of cardiovascular disease. The vascular endothelium is a multifunctional organ system composed of metabolically active and physiologically responsive component cells that carefully regulate blood flow according to metabolic conditions. Lifestyle modification, particularly aerobic exercise and dietary adjustment, has a positive effect on vascular aging.

A new study from the University of Tsukuba investigated the effects of curcumin in 32 post-menopausal women divided into one of three groups.4 The first group was the control  group, the second group took part in an aerobic training schedule, and  the third group was given a curcumin supplement on a daily basis. The  curcumin used in the study was highly bioavailable (with up to 300 times  increased bioavailability compared to raw turmeric) and in colloidal  nanoparticle form, given at a daily dosage of 25 mg. The study duration  was for eight weeks. Over the course of the study, the results demonstrated that  blood vessel dilation increased equally and to a notable extent in the exercise  and the curcumin group. No changes were apparent in the control group. These results indicated that curcumin ingestion and aerobic exercise training can increase flow-mediated dilation in postmenopausal women, suggesting that both can potentially improve the age-related decline in endothelial function and therefore improve exercise performance.4

Reducing Exercise-Induced Oxidative Stress Oxidative stress occurs on an ongoing basis as the body comes into contact with oxygen. It occurs as a result of necessary body functions such as eating, breathing and moving. Caloric restriction reduces oxidative stress and promotes longevity by
reducing the number of reactions that occur in the body as a result of the digestive process. During digestion, the molecules from food become oxidized; they lose an electron and become unstable. If they are not neutralized or “cleaned up” by the body, they cause damage to other cells. This form of stress causes us to age faster and to feel the pains of aging and of overtraining. Reducing oxidative stress is paramount for improving athletic performance, recovery time and overall health. Eating healthfully, reducing stress and supplementing appropriately can all help to reduce the level of oxidative stress the body is under. Curcumin has been demonstrated to significantly reduce oxidative stress within the body, with some of the research focusing on curcumin’s beneficial role in
cadioprotection.

Another study investigated the effects of curcumin supplementation on exercise-induced oxidative stress in humans. Ten male participants were asked to take part in three phases of the study in random order. They were a part of any of the following groupings that took a treatment before or after exercise: 1) placebo (control), 2) single (curcumin only before exercise) and 3) double (curcumin before and immediately after exercise). Each participant received oral administration
of 90 mg of curcumin or the placebo two hours before exercise and immediately after exercise. Blood samples that were taken pre and post exercise indicated that curcumin increased blood
antioxidant capacity and can reduce exercise-induced oxidative stress.5

Curcumin also raises glutathione levels in the body; glutathione is the body’s chief antioxidant.

Studies to learn more about the effects of curcumin in the body after exercise have been conducted in humans and animals.2,5 Intensive exercise such as downhill running can cause muscle fiber damage, inflammation and delayed onset muscle soreness (DOMS). Curcumin reduces exercise-related inflammation and improves running performance recovery in mice, according to a recent study.2

The animals received either curcumin or placebo and were assigned to run either uphill or downhill on a treadmill for 2.5 hours. Two-to-three days later, they were placed on a treadmill and allowed to run to fatigue, with time to fatigue recorded. In a second experiment, voluntary running on an activity wheel was monitored in another subset of animals, while a third experiment analyzed muscle tissue for inflammatory cytokines after the forced running exercises in additional mice. The research team found that downhill running increased inflammatory cytokines, decreased voluntary activity, and shortened the animals’ run time to fatigue.2 However, curcumin was able to offset these effects. The results of the study clearly demonstrate that curcumin is able to reduce inflammation and offset some of the performance deficits associated with exercise-induced muscle damage.

Inflammation and Muscle Damage Due to Exercise

It is well understood that intense exercise can cause inflammation and muscle damage depending on the duration, intensity and mode of exercise. Curcumin is able to attenuate inflammation by targeting several factors including growth regulators, cell signalling molecules and transcription factors, proteins that regulate the flow of genetic information in the cells.8

Inflammation is a condition that involves uncontrolled activated immune responses. Numerous studies have suggested that curcumin is able to modulate the immune response and play an important role in the treatment of inflammation and metabolic diseases. Results from both in-vitro and in-vivo studies have provided strong evidence towards the therapeutic potential of curcumin. This research has also identified multiple biological targets and intricate mechanisms of action that characterize curcumin as a potent ‘drug’ for numerous ailments. Curcumin can modulate the functional influence of immune cells and the related cross-talk during inflammation to improve immune status against diseases.

As a potent antioxidant and powerful anti-inflammatory, curcumin has several mechanisms of action in the body that help to improve physical performance and general health. Studies have demonstrated that curcumin is able to modulate the immune system, put out the fires of inflammation, and decrease muscle soreness for improved recovery time. It acts to improve endothelial function to the same extent that an aerobic exercise regimen can. Both animal and human studies have highlighted numerous benefits of curcumin and future research will likely identify others.

What You Need to Know

Curcumin is a powerful cellular protector that can have very beneficial and positive exercise performance effects in people who are active. This well-known and potent natural antioxidant ingredient derived from the turmeric root is able to reduce and prevent inflammation and also provide a performance boost by modulating the immune system, decreasing muscle soreness to improve recovery time, and also by enhancing endothelial function in the same manner as exercise does. Curcumin is a safe and effective exercise recovery enhancer, and it even produces some of the same cardiovascular benefits as aerobic exercise itself.