Studies have shown that Montmorency sour cherries may help reduce muscle soreness and accelerate regeneration, which is why they are enjoying increasing popularity among athletes. Studies found positive effects for recovery in sports, especially in the disciplines of long-distance running, cycling, sprinting, field sports and strength training.
Two studies were conducted by Texas A&M University Department of Kinesiology to evaluate the effects of powdered tart cherry supplementation on strenght and endurance athletes. Subjects in both studies were taking tart cherry supplements which contained 480 mg of freeze dried Montmorency tart cherry powder (CherryPURE).
The first study’s aim was to determine whether short-term consumption of a powdered tart cherry supplement before and after intense resistance-exercise attenuates muscle soreness and recovery strength loss while lowering markers of muscle damage, inflammation, and oxidative stress. The study was conducted on 23 healthy, resistance-trained men.
The study concluded by saying that “short-term supplementation of Montmorency powdered tart cherries surrounding a single bout of resistance exercise, appears to be an effective dietary supplement to attenuate muscle soreness, strength decrement during recovery, and markers of muscle catabolism in resistance trained individuals.” 
The second study was conducted on 27 endurance-trained runners or triathletes. It concluded that there is a significant potential with powdered tart cherry supplementation, due to its attenuating effects when it comes to inflammatory markers over a 48-h recovery period.
The researchers found also that, “coupled with the dampening of the inflammatory response, the powdered tart cherry subjects seemed to better maintain post-run redox balance compared to placebo supplemented subjects.” 
In conclusion, the study states that “the primary findings of the current study demonstrate that powdered tart cherry supplementation in endurance-trained individuals provides similar benefits as previously studied tart cherry juices or concentrates following acute bouts of aerobic-based exercise.”
A meta-analysis published in the International Journal of Sport Nutrition and Exercise Metabolism suggests that sour cherry supplementation leads to improved muscle recovery and a reduction in sore muscles. Improved muscle recovery in sports such as after high jump training has been demonstrated via supplementation with tart cherries. With regard to sore muscles, positive effects on the inflammation markers C-reactive protein and interleukin 6 were observed. 
In the first study of the effects of tart cherries on exercise, male college students consumed either 350 ml of tart cherry juice or a placebo drink twice a day for eight days, and did strenuous weight lifting on day four of the study. The subjects in the tart cherry group reported significantly less pain compared to the placebo group. Apart from these benefits on recovery in sports, the average loss of strength during the four days after the exercise was 22% with the placebo, but only 4% with the sour cherry concentrate. 
In a study by Oregon Health and Science University, male and female runners were given 310 ml of Montmorency tart cherry juice or a placebo drink twice a day 7 days before and on the day of the 199-mile relay run. Compared to the placebo group, the athletes who consumed sour cherry juice had less subjectively assessed muscle pain after the race. 
A similar study was carried out at the London Marathon. Within the tart cherry juice group, a faster recovery of strength and reduced inflammation markers could be observed compared to the placebo group. 
In the UK, researchers took measurements on cyclists who consumed either 30 ml of Montmorency tart cherry juice or a placebo drink twice a day for seven days. On days 5, 6 and 7 of the study, the participants exercised in the form of high-intensity cycling intervals. It was found that the markers for inflammation and oxidative stress (C-reactive protein and uric acid) were significantly lower if the cyclists regularly consumed tart cherry juice. 
Another study of cyclists found that if the athletes consumed Montmorency sour cherry concentrate, systolic blood pressure could be lowered and peak performance increased by an average of 9.5%. 
The studies that have already been carried out on Montmorency tart cherries and their effects on recovery in sports show a variety of positive effects. During strength training, running, cycling and field sports, subjects who consumed tart cherries complained less often of sore muscles than the comparison group. This effect was confirmed by measuring inflammation markers in the blood. Generally, a faster recovery of strength and an increase in peak performance in the sour cherry group was also measurably experienced.