Here are two well-established findings concerning exercise and your immune system: First, moderate exercise boosts your immune system, thereby making you less susceptible to colds and other forms of sickness. Second, hard exercise, such as an intense track session or an especially long run, temporarily compromises your immune system. That’s why it’s common to come down with a cold when you’re training hard. And that’s why part of post-workout recovery, such as taking in carbohydrates soon after a particularly draining session, centres on bolstering your immune system.
New research suggests adding another arrow to your post-workout recovery quiver, namely, ginger, which lowered markers of inflammation in runners in a study published in the Central European Journal of Immunology.
Iranian researchers gathered 28 well-trained male runners for a 12-week training block. The subjects were young (average age of 23), fit (average VO2 max of 67, a level commonly found in national-class competitors) and lean (average size of about 173cm, 65kg); they were used to training hard.
Throughout the hard 12-week cycle, all the runners did the same training. After six weeks, they did a treadmill run to exhaustion, in which they started at a 10% grade, and kept running as long as possible while the incline and pace were increased every three minutes. Immediately after the treadmill test, the researchers measured plasma levels of three types of cytokines, which are hormone-like proteins that are considered markers of inflammation. As expected, the runners showed elevated levels of these cytokines after the treadmill test six weeks into their training.
For the final six weeks of the training cycle, half the runners took 500 milligrams of powdered ginger three times a day (in pill form that didn’t taste or smell like ginger), while the other half took a placebo.
At the end of the training cycle, the runners repeated the treadmill test to exhaustion. When the researchers then measured the runners’ cytokine levels, the differences between the groups was striking.
In the placebo group, cytokine levels were 32% greater than they’d been after the treadmill test six weeks earlier. This finding suggests that the runners’ immune systems were increasingly challenged by bouts of hard running. In theory, this would increase their susceptibility to upper respiratory tract infections, just when, in many schedules, they’d be getting ready for their key races.
In the ginger group, cytokine levels were 18% lower than they’d been post-treadmill test six weeks earlier. That is, if anything, their immune systems were stronger than they’d been halfway through their training cycle. In theory, this would lessen their susceptibility to getting sick as their key competitions neared.
The researchers attributed their findings to ginger’s anti-inflammatory properties, which they said mimic those of common anti-inflammatory medications but without the drugs’ side effects.
Ginger is widely available as a supplement in capsule or powdered form. A 2.5cm piece of crystallised ginger contains about 500 milligrams of ginger, while a cup of strong ginger tea contains about 250 milligrams.