The first form of flexibility to develop in a periodized program is optimal levels of static passive flexibility (the range of motion is produced by force from a muscle group other than the agonist or from an external source).
PS: My recommended introduction to periodization is our free video course “The Most Useful Definition of Periodization and The 4 Reason that you MUST base your programs on Periodization if you want to see the best possible results for your athletes/clients”. Get it at www.yestostrength.com (email required)
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