{
  "wireMagic": "pb3",
  "pens": [ {
  
  } ],
  "wsWinStyles": [ {
  
  } ],
  "wpWinPositions": [ {
  
  } ],
  "events": [ {
    "tStartMs": 6961,
    "dDurationMs": 2669,
    "segs": [ {
      "utf8": "Here we have an athlete\npreparing for a game."
    } ]
  }, {
    "tStartMs": 9714,
    "dDurationMs": 2419,
    "segs": [ {
      "utf8": "They’ve put on their gear\nand done their warmup,"
    } ]
  }, {
    "tStartMs": 12216,
    "dDurationMs": 3629,
    "segs": [ {
      "utf8": "and now it’s time for one\nmore routine— stretching."
    } ]
  }, {
    "tStartMs": 16012,
    "dDurationMs": 4463,
    "segs": [ {
      "utf8": "Typically, athletes stretch before\nphysical activity to avoid injuries"
    } ]
  }, {
    "tStartMs": 20475,
    "dDurationMs": 2085,
    "segs": [ {
      "utf8": "like muscle strains and tears."
    } ]
  }, {
    "tStartMs": 22727,
    "dDurationMs": 3045,
    "segs": [ {
      "utf8": "But does stretching actually prevent\nthese issues?"
    } ]
  }, {
    "tStartMs": 25855,
    "dDurationMs": 3754,
    "segs": [ {
      "utf8": "And if so, how long do the benefits\nof stretching last?"
    } ]
  }, {
    "tStartMs": 30276,
    "dDurationMs": 1543,
    "segs": [ {
      "utf8": "To answer these questions,"
    } ]
  }, {
    "tStartMs": 31819,
    "dDurationMs": 3754,
    "segs": [ {
      "utf8": "we need to know what's actually happening\nin the body when we stretch."
    } ]
  }, {
    "tStartMs": 35740,
    "dDurationMs": 3337,
    "segs": [ {
      "utf8": "There are two kinds of stretching\nour athlete might be doing."
    } ]
  }, {
    "tStartMs": 39118,
    "dDurationMs": 2628,
    "segs": [ {
      "utf8": "Dynamic stretches,\nwhich are controlled movements"
    } ]
  }, {
    "tStartMs": 41746,
    "dDurationMs": 2753,
    "segs": [ {
      "utf8": "that engage a range of muscles\nthroughout the motion."
    } ]
  }, {
    "tStartMs": 44665,
    "dDurationMs": 3129,
    "segs": [ {
      "utf8": "And static stretches, \nwhere the stretcher holds a position"
    } ]
  }, {
    "tStartMs": 47794,
    "dDurationMs": 3837,
    "segs": [ {
      "utf8": "to keep specific muscles\nat a fixed length and tension."
    } ]
  }, {
    "tStartMs": 51881,
    "dDurationMs": 3754,
    "segs": [ {
      "utf8": "Our athlete is currently doing\na static hamstring stretch—"
    } ]
  }, {
    "tStartMs": 55676,
    "dDurationMs": 3337,
    "segs": [ {
      "utf8": "a 30 second interval \nwhere he pulls his hamstring"
    } ]
  }, {
    "tStartMs": 59013,
    "dDurationMs": 2252,
    "segs": [ {
      "utf8": "beyond its usual range of motion."
    } ]
  }, {
    "tStartMs": 61390,
    "dDurationMs": 2628,
    "segs": [ {
      "utf8": "However, while we often think \nof stretching a muscle"
    } ]
  }, {
    "tStartMs": 64018,
    "dDurationMs": 1960,
    "segs": [ {
      "utf8": "like stretching a rubber band,"
    } ]
  }, {
    "tStartMs": 65978,
    "dDurationMs": 3671,
    "segs": [ {
      "utf8": "muscles are actually comprised\nof various tissue types,"
    } ]
  }, {
    "tStartMs": 69649,
    "dDurationMs": 3044,
    "segs": [ {
      "utf8": "which interact to make a complex material."
    } ]
  }, {
    "tStartMs": 72985,
    "dDurationMs": 3462,
    "segs": [ {
      "utf8": "Rubber is elastic, meaning \nit resists being stretched"
    } ]
  }, {
    "tStartMs": 76572,
    "dDurationMs": 2336,
    "segs": [ {
      "utf8": "and then returns to its original shape."
    } ]
  }, {
    "tStartMs": 79033,
    "dDurationMs": 2461,
    "segs": [ {
      "utf8": "But muscle is viscoelastic."
    } ]
  }, {
    "tStartMs": 81661,
    "dDurationMs": 3336,
    "segs": [ {
      "utf8": "This means that, in addition\nto those elastic qualities,"
    } ]
  }, {
    "tStartMs": 85164,
    "dDurationMs": 3629,
    "segs": [ {
      "utf8": "muscle changes under the stress\nof being stretched."
    } ]
  }, {
    "tStartMs": 89168,
    "dDurationMs": 1335,
    "segs": [ {
      "utf8": "Let’s see this in action."
    } ]
  }, {
    "tStartMs": 90628,
    "dDurationMs": 4838,
    "segs": [ {
      "utf8": "At the large scale, this hamstring stretch\nis pulling on layers of protective tissue"
    } ]
  }, {
    "tStartMs": 95466,
    "dDurationMs": 1710,
    "segs": [ {
      "utf8": "surrounding the muscle fibers,"
    } ]
  }, {
    "tStartMs": 97176,
    "dDurationMs": 4129,
    "segs": [ {
      "utf8": "as well as the tendons that connect\nthis muscle to nearby bones."
    } ]
  }, {
    "tStartMs": 101639,
    "dDurationMs": 4963,
    "segs": [ {
      "utf8": "These tissues contain elastic proteins\nlike collagen and elastin,"
    } ]
  }, {
    "tStartMs": 106602,
    "dDurationMs": 4171,
    "segs": [ {
      "utf8": "which allow them to slightly elongate\nover the duration of the stretch."
    } ]
  }, {
    "tStartMs": 111607,
    "dDurationMs": 4046,
    "segs": [ {
      "utf8": "At the smaller scale, these skeletal\nmuscle fibers are comprised"
    } ]
  }, {
    "tStartMs": 115653,
    "dDurationMs": 2252,
    "segs": [ {
      "utf8": "of millions of sarcomeres—"
    } ]
  }, {
    "tStartMs": 117989,
    "dDurationMs": 3253,
    "segs": [ {
      "utf8": "the smallest contracting unit\nof muscle tissue."
    } ]
  }, {
    "tStartMs": 121909,
    "dDurationMs": 5172,
    "segs": [ {
      "utf8": "Sarcomere’s long, fibrous proteins can\nrelax to elongate muscle fibers"
    } ]
  }, {
    "tStartMs": 127165,
    "dDurationMs": 2711,
    "segs": [ {
      "utf8": "or they can contract to shorten them—"
    } ]
  }, {
    "tStartMs": 129876,
    "dDurationMs": 2419,
    "segs": [ {
      "utf8": "pulling on tendons and protective tissue"
    } ]
  }, {
    "tStartMs": 132295,
    "dDurationMs": 3086,
    "segs": [ {
      "utf8": "to create the force\npropelling our athlete’s body."
    } ]
  }, {
    "tStartMs": 135965,
    "dDurationMs": 2419,
    "segs": [ {
      "utf8": "And when those tissues have\nbeen stretched out,"
    } ]
  }, {
    "tStartMs": 138384,
    "dDurationMs": 3128,
    "segs": [ {
      "utf8": "they retain their strength\nat longer lengths,"
    } ]
  }, {
    "tStartMs": 141596,
    "dDurationMs": 4629,
    "segs": [ {
      "utf8": "allowing our athlete to take full\nadvantage of his improved range of motion."
    } ]
  }, {
    "tStartMs": 146934,
    "dDurationMs": 4838,
    "segs": [ {
      "utf8": "Unlike a rubber band, this muscle’s\nresistance to stretching decreases"
    } ]
  }, {
    "tStartMs": 151772,
    "dDurationMs": 1877,
    "segs": [ {
      "utf8": "with each 30 second stretch,"
    } ]
  }, {
    "tStartMs": 153649,
    "dDurationMs": 3712,
    "segs": [ {
      "utf8": "allowing our athlete\nto continually elongate his hamstring."
    } ]
  }, {
    "tStartMs": 157820,
    "dDurationMs": 3837,
    "segs": [ {
      "utf8": "And this improved flexibility\nlikely decreases the chance"
    } ]
  }, {
    "tStartMs": 161657,
    "dDurationMs": 2378,
    "segs": [ {
      "utf8": "of incurring certain muscle injuries."
    } ]
  }, {
    "tStartMs": 164160,
    "dDurationMs": 2461,
    "segs": [ {
      "utf8": "But due to muscle’s elastic properties,"
    } ]
  }, {
    "tStartMs": 166621,
    "dDurationMs": 4296,
    "segs": [ {
      "utf8": "this effect will be gone in just \n10 minutes without further activity."
    } ]
  }, {
    "tStartMs": 171334,
    "dDurationMs": 3753,
    "segs": [ {
      "utf8": "The exercise from his match should\nelevate his muscle’s temperature"
    } ]
  }, {
    "tStartMs": 175087,
    "dDurationMs": 2169,
    "segs": [ {
      "utf8": "and continue elongating the muscle,"
    } ]
  }, {
    "tStartMs": 177256,
    "dDurationMs": 3170,
    "segs": [ {
      "utf8": "maintaining his increased flexibility\nthroughout the game."
    } ]
  }, {
    "tStartMs": 180801,
    "dDurationMs": 2545,
    "segs": [ {
      "utf8": "But once he gives his hamstrings a break,"
    } ]
  }, {
    "tStartMs": 183346,
    "dDurationMs": 2586,
    "segs": [ {
      "utf8": "they’ll retract back \nto their previous state."
    } ]
  }, {
    "tStartMs": 186641,
    "dDurationMs": 2002,
    "segs": [ {
      "utf8": "So if all this is just temporary,"
    } ]
  }, {
    "tStartMs": 188768,
    "dDurationMs": 3003,
    "segs": [ {
      "utf8": "how can you permanently improve \nyour flexibility?"
    } ]
  }, {
    "tStartMs": 192021,
    "dDurationMs": 4922,
    "segs": [ {
      "utf8": "For skeletal muscles, improved flexibility\ncomes from additional sarcomeres,"
    } ]
  }, {
    "tStartMs": 197026,
    "dDurationMs": 3295,
    "segs": [ {
      "utf8": "which allow you to maintain strength\nat even greater lengths."
    } ]
  }, {
    "tStartMs": 200529,
    "dDurationMs": 2962,
    "segs": [ {
      "utf8": "Sarcomeres are added and subtracted\nto muscles"
    } ]
  }, {
    "tStartMs": 203491,
    "dDurationMs": 2461,
    "segs": [ {
      "utf8": "depending on how frequently they’re used,"
    } ]
  }, {
    "tStartMs": 206077,
    "dDurationMs": 4963,
    "segs": [ {
      "utf8": "so improving overall flexibility requires\na comprehensive stretching regimen."
    } ]
  }, {
    "tStartMs": 211374,
    "dDurationMs": 3336,
    "segs": [ {
      "utf8": "Plus, you need to stretch often—\nvery often."
    } ]
  }, {
    "tStartMs": 214961,
    "dDurationMs": 4754,
    "segs": [ {
      "utf8": "Current research suggests at least \n10 minutes a day for roughly two months."
    } ]
  }, {
    "tStartMs": 219840,
    "dDurationMs": 3170,
    "segs": [ {
      "utf8": "And since it's unsafe to hold\nany stretch for too long,"
    } ]
  }, {
    "tStartMs": 223010,
    "dDurationMs": 4380,
    "segs": [ {
      "utf8": "it's recommended that you break up your\nstretching within any given session."
    } ]
  }, {
    "tStartMs": 227723,
    "dDurationMs": 3462,
    "segs": [ {
      "utf8": "Frequent stretching also makes lasting\nchanges to your brain."
    } ]
  }, {
    "tStartMs": 231394,
    "dDurationMs": 4379,
    "segs": [ {
      "utf8": "The more you stretch a muscle,\nthe higher your pain threshold becomes,"
    } ]
  }, {
    "tStartMs": 235898,
    "dDurationMs": 2461,
    "segs": [ {
      "utf8": "allowing you to stretch\nfurther and further."
    } ]
  }, {
    "tStartMs": 238985,
    "dDurationMs": 2627,
    "segs": [ {
      "utf8": "Long-term improvements \nto your flexibility can provide"
    } ]
  }, {
    "tStartMs": 241612,
    "dDurationMs": 2086,
    "segs": [ {
      "utf8": "a better range of motion for your joints,"
    } ]
  }, {
    "tStartMs": 243698,
    "dDurationMs": 4337,
    "segs": [ {
      "utf8": "potentially reducing your risk of muscle\ninjury in the short and long-term."
    } ]
  }, {
    "tStartMs": 248327,
    "dDurationMs": 2378,
    "segs": [ {
      "utf8": "But it’s also possible\nto stretch too much,"
    } ]
  }, {
    "tStartMs": 250705,
    "dDurationMs": 4421,
    "segs": [ {
      "utf8": "as flexible people can move their joints\nin potentially dangerous ways."
    } ]
  }, {
    "tStartMs": 255584,
    "dDurationMs": 3379,
    "segs": [ {
      "utf8": "Stretching also isn't helpful\nfor every kind of movement,"
    } ]
  }, {
    "tStartMs": 258963,
    "dDurationMs": 3128,
    "segs": [ {
      "utf8": "especially those where muscle\ninjuries aren't very common."
    } ]
  }, {
    "tStartMs": 262383,
    "dDurationMs": 4463,
    "segs": [ {
      "utf8": "For example, long distance running only\ninvolves a small range of motion"
    } ]
  }, {
    "tStartMs": 266846,
    "dDurationMs": 1376,
    "segs": [ {
      "utf8": "for the joints involved,"
    } ]
  }, {
    "tStartMs": 268222,
    "dDurationMs": 4254,
    "segs": [ {
      "utf8": "so stretching is unlikely to prevent\nthat sport’s most common injuries."
    } ]
  }, {
    "tStartMs": 272893,
    "dDurationMs": 1377,
    "segs": [ {
      "utf8": "When it comes down to it,"
    } ]
  }, {
    "tStartMs": 274270,
    "dDurationMs": 3253,
    "segs": [ {
      "utf8": "different lifestyles require \ndifferent kinds of mobility."
    } ]
  }, {
    "tStartMs": 277648,
    "dDurationMs": 4713,
    "segs": [ {
      "utf8": "And no single stretching regimen is\nflexible enough to fit every situation."
    } ]
  } ]
}