Nice Legs, Great Squat

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A presentation on squat research and the do\'s and don\'t of good squatting

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Nice Legs, Great Squat

  1. 1. Mark McKean PhD CSCS<br />Nice Legs, Great Squat<br />
  2. 2. Session Summary<br />This session will <br />review the misconceptions of the squat. <br />show you how to assess your own technique and improve your squat.<br />teach you how to progress the squat exercise for your clients. <br />look at the top 5 Squat derivatives and when not to use them.<br />
  3. 3. Back Squat Misconceptions<br />
  4. 4. Misconception 1do not squat deep<br />Most research has been conducted on partial or parallel squats and focus on one joint not the whole pattern.<br />No affect on knee stability in elite power lifters and weight lifters (Chandler, et al. 1989).<br />Partial squats increase forward trunk lean (Fry, et al.2003). <br />Partial squats used in all knee research studiesso hard to say deep squats cause knee problems<br />
  5. 5. Deep squats are more valuable for <br />increased thigh hypertrophy (Colker, et al. 2002) <br />and increased concentric contraction of the Gluteus Maximus muscle (Caterisano, et al. 2002).<br />
  6. 6. My Research<br />Squat movement patterns remain coordinated through deep squat movements<br />Both male and female experienced squatters will squat deep when allowed to squat in a natural unrestricted squat movement<br />
  7. 7. Misconception 2hip & Knee angles-different<br />Peak hip angles have been reported as achieving 95o in daily lifting activities (Hemmerich, et al. 2006), to as little as 34oflexion in squatting (Dahlkvist, et al. 1982, Wretenberg, et al. 1996).<br />The peak knee angles have been reported as ranging from 78o (Miletello,et al. 2006) for top level power lifters to as little as 35-40o flexion in cadaveric cruciateligament studies (Toutoungi, et al. 2000)<br />No researchcomparing timing and coordination of the two joints.<br />
  8. 8. My Research<br />Hip Joint maximum angle and normalised time (mean and standard error)<br />
  9. 9. Knee joint maximum angle and normalised time (mean and standard error)<br />
  10. 10. When subjects squatted with no restriction on knee angles, forward knee movement, or depth of the squat, all subjects reached their maximum hip and knee angles within 2% of the deepest part of the squat regardless of load and gender.<br />Hip-knee joint coordination strategy is a dominant over riding component of the squatting pattern of movement which is maintained regardless of variations to load – i.e. if you inhibit the knee the hip takes over.<br />
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  12. 12. Females tend to be more synchronised for the hip-knee inter-joint coordinated movement of squatting <br />Heavier loads allow males to squat deeper and in a more synchronised manner.<br />
  13. 13. Misconception 3Neutral spine when squatting<br />Research in this area is limited and all squat papers suggest recommended lumbar spine position as being “flat to arched but not rounded” (Morrissey, et al. 1998).<br />In the few cases where the subjects were instructed on a best or correct lumbar position when performing the squat, the lumbar curve, and any change in its position throughout the squat, was not actually monitored or measured during the performance.<br />The key study by Walsh, et al. 2007, used parallel squats and showed a decrease in lumbar flexion during descent<br />
  14. 14. My Research<br />Commencement angles for all squat styles<br />
  15. 15. Lumbar Flexion - start, maximum, and timing (mean and standard error)<br />
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  17. 17.
  18. 18. As soon as the bar was loaded onto the shoulders all subjects lost their normal lumbar curve and became straight or kyphotic.<br />The lumbar spine tends to centralise its position based on the adjustments made to the placement of the bar on a subjects shoulders, and the movement occurring at the sacrum.<br />
  19. 19. Misconception 4different stance widths<br />Conflicting results with some studies showing no noticeable change in muscle recruitment (Escamilla, et al. 2001, Signorile, et al. 1995) and others finding width of stance did affect muscle recruitment patterns (McCaw, et al. 1999)<br />Escamilla et al. showed no significant differences in trunk lean between three different widths of stance but slight variations in hip and knee moments (Escamilla, et al. 2001).<br />
  20. 20. My Research<br />The wider stance allowed all subjects to achieve reduced lumbar, sacrum and lumbar flexion angles, whilst the NS squat caused increased lumbar and sacrum angles as well as increased lumbar flexion.<br />
  21. 21. Lumbar-Pelvic ratios (mean and standard deviation).<br />
  22. 22. Misconception 5movement same both phases<br />No research comparing differences between ascent and descent squat movements<br />There has been little research to determine if different tempos create changes in joint coordination and timing in the different phases.<br />Walsh et al. reported differences in lumbar segment behaviour for each phase (Walsh, et al. 2007), while Escamilla found differences in the extent to which the trunk leant forward at similar knee flexion angles in each phase (Escamilla, et al. 2001). <br />
  23. 23. My Research<br />Times for each phase of BW and BW+50% (mean and standard deviation)<br />
  24. 24. Misconception 7Knees stay behind toes<br />No affect on knee stability was found from long term deep squatting as evidenced in elite power lifters and weight lifters (Chandler, et al. 1989). <br />The study by Fry et al. showed that the technique of restricted forward knee movement adjusted the squat movement pattern (Fry, et al.2003). <br />The restricted knee position also produced more anterior upper body lean as well as an increased hip angle when compared to the unrestricted squat technique.<br />
  25. 25. Haggard et al. suggested that early movement of one joint may set up joint rotations in partner joints that make multi-joint movements more efficient (Haggard, et al. 1995).<br />Any restriction placed on the knee movement in the squat exercise will result in mechanical changes at the hip and knee (Fry, et al. 2003)<br />
  26. 26. My Research<br />Knee maximum forward position and normalised time (mean and standard error)<br />
  27. 27. Time when knees moved forward of toes (mean and standard deviation)<br />
  28. 28. All subjects moved forward of the toes before the descent phase had reached half way and then remained forward of the toes until approximately half way back to the top during the ascent.<br />People self adjust actual joint movements in an attempt to maintain the synchronised coordination of the hip and knee<br />
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  30. 30. The early time at which the knees move forward of the toes and the late return behind the toes, also suggests that forward movement of the knees may be the fundamental movement that determines the pattern for squatting. <br />The earlier time at which the knees reach their maximum forward position also suggests that the knee position must be established early to allow the angular motion of the knee and hip to occur in a more synchronised joint rotation pattern.<br />
  31. 31. Misconception 6 No Gender Differences<br />The majority of studies have shown significant difference in general movement patterns and actions between genders (Ford, et al. 2005, Kernozek, et al. 2005, Lindbeck, et al. 2001, Yu, etal. 2005) but nothing on squats.<br />Further research into industrial lifting techniques and lower limb activities has also shown that men and women adjust to loads and tasks differently (Decker, et al.2003, O’Brien, et al. 2005, Zeller, et al. 2003).<br />
  32. 32. Gender differences in the pelvic dimensions (Brinckmann, et al. 1981, Mays, et al. 2000), lumbar vertebrae sizes (Gilsanz, et al. 1994), and trunk geometry (Marras, et al. 2001) have been reported in the literature. <br />Yet little gender differences exist in Q angles; less than 2.3o - which has been attributed to difference in height (Grelsamer, et al. 2005); and only a slight difference in ASIS width of 0.1 cm (Jackson, et al. 2000).<br />
  33. 33. Research suggests that squat patterns would be different for genders, but it does not appear in literature on back squats.<br />
  34. 34. My Research<br />As the load increased from BW squats to BW+50%, males adjusted hip and knee angles by increasing flexion depth to accommodate the loads, thus altering the relative angles of these two key joints whilst at the same time maintaining the timing of when these maximum angles occur.<br />In order to squat, it appears that males have a lower range of movement at the sacrum, and this is compensated by an increased range of movement in lumbar flexion.<br />
  35. 35. Females may need to maintain a greater dynamic stiffness in the lumbar flexion angle and make up for this by an increased range of movement in the sacrum.<br />
  36. 36. Assessing Squat Technique<br />
  37. 37. Set Up<br />Wide stance<br />Bar resting on shoulders<br />No cueing or technique guidelines<br />Squat deep as feel comfortable<br />
  38. 38. Observation Points<br />Changes in lumbar spine bar or not<br />Knees over toes early<br />Timing of hip and knees should be synced max<br />Men change lumbar angle – women change sacrum angle<br />Loads improve men’s coordination<br />
  39. 39. how to develop and progress the squat technique<br />
  40. 40. Include in all Programs<br />Wider stance is best to start with<br />Start unloaded and progress squat depth and control with no load<br />Go as low as client can control<br />Use DB to start with loads to reinforce pattern<br />Use stick across shoulder before Bar<br />Allow time for client to learn how to squat deep with one load before increasing<br />
  41. 41. top 5 Squat derivatives<br />
  42. 42. Front Squat<br />Increase vertical alignment of the trunk<br />Changes hip and knee angles by reducing hip flexion and increasing knee flexion<br />Greatest restriction often occurs through lack of shoulder flexibility<br />
  43. 43. Deadlift<br />Allows multiple progressions<br />Hang deadlift – DB, bar, stick<br />Full deadlift – DB, bar, Stick<br />Single leg deadlift – DB, bar<br />Straight leg and bent leg versions<br />Progressions to Power Clean movements<br />Altered synchronisation of hip and knee movement<br />
  44. 44. Lunge<br />Increased stability of pelvis required – less stable and more balance required, but can achieve deeper knee flexion<br />Multiple progressions<br />Stationary lunge with DB, stick, bar<br />Forward lunge with DB, stick, bar, short, long<br />Reverse lunge with DB, stick, bar, short, long <br />Side lunge with DB, stick, bar, short, long<br />Multiple lunges – walking, or skipping<br />Lunge with rotation – DB, stick, med ball<br />
  45. 45. Step up<br />Increased stability of pelvis required to transition weight from one foot to the other whether low to high or high to low. Changes development of knee structural strength and provides for single leg weight bearing in short bursts.<br />Multiple progressions<br />Step up with DB, stick, bar, low to high box<br />Side step up with DB, stick, bar, low to high box<br />Diagonal step up stick, bar, low to high box<br />Dynamic step up to high knee action <br />Step up to single foot take off and landing<br />
  46. 46. Split Squat<br />Allows for a loading of back leg, front leg or even distribution. Multiple bar positions and foot placements<br />Multiple progressions<br />Split squat with DB, stick, bar, feet on parallel<br />Split squat with DB, stick, bar, feet on diagonal<br />Split squat with DB, stick, bar, rear foot raised<br />Split squat with DB, stick, bar, front foot raised<br />Progressive over low to high steps<br />
  47. 47. Mark McKean<br />Post Doctoral Research Fellow <br />Australian Institute of Fitness Research<br />University of Sunshine Coast<br />mmckean@usc.edu.au<br />

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