Muscle Tightness from Lack of Stability

Question:

I have been training a client with incredibly tight calves, hamstrings, glutes, lower back and pectorals. While stretching his hams and glutes, he will usually feel it in his lower back before the targeted area. He's tried Pilates, sports massage and physio, but not much progress has been made. He's a professional photographer and has had to carry heavy equipment for a long time, which has adversely affected his posture and flexibility. How can I help this person improve his flexibility?

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