Ever since training for and completing the London marathon two years ago, Jess Pritchard has been left with a nagging feeling that's been hard to shift.

“What started as a small niggle in my lower back turned into a persistent issue day-to-day,” the certified trainer and group exercise instructor tells Fit&Well .

An imbalance between her left glute, lower back and core became exacerbated by training and teaching Spin classes until the only option was to stop. You may like

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“Over time I realized I needed to rebuild the strength and control a

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