It can be caused by a number of factors, including a rapid increase in the frequency of training, sudden increase in the intensity of training, transition from one training method to another, genetic abnormalities of the knee joint and poor base strength of the quadriceps.

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Although figures are hard to come by, the intensity of their training programs indicates just how seriously the Chinese are taking a potential fairway to medals.

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The widely available equations for calculating heart rate training zones may not be specific enough to help you significantly improve performance, but they do provide a starting point, and when combined with a heart rate monitor, they can help you more accurately assess and monitor the intensity of your training sessions.

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In addition to CrossFit, Schaefer supplements his training with SoulCycle classes and other forms of high-intensity training.

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Ultimately, the proliferation of interval training and other high-intensity protocols has saved a lot of time and burned a lot of fat for fitness enthusiasts worldwide.

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The laid-back atmosphere at spring training doesn't compare to the intensity level of the WBC games where there's so much pride at stake playing for your country.

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The six-second bursts are one of the shortest sprint durations ever used in high-intensity training (HIT).

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The best training program for biking, running or swimming will always be a mix of hard intensity and long easy recovery and base-building rides.

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