Weight distribution and centre of pressure excursion during the golf putt

Hurrion and Hurrion (2008) examined weight distribution in thirty elite PGA professional golfers and thirty amateur golfers with a handicap between (+3 to 9), a twenty-five foot putt was holed until there were 6 successful attempts. The main significant kinematic difference found between the two subject groups was in set up; the professionals weight distribution was 48.34% left foot and 51.66% right foot, whereas the amateurs weight distribution was 40.57% left foot 59.60% (Hurrion & Hurrion, 2008). Hurrion and Hurrion (2008) found a significant difference also lied in the total amount of sway between the two groups, the amateur group had a total sway of 83.10mm and the professionals had a total sway of 64.34mm. McLaughlin et al. (2008) also observed significant differences in centre of pressure movement for a 4m putt, the high handicap

group (18 – 27) produced significantly more CP excursion (right to left) in the downswing phase (Study Two, Figure 4.1, pp. 62) with a value of 10.7mm, in comparison the LH group (0 – 9) was 4.5mm and the Mid handicap group (MH) CP excursion was 5.5mm. Hurrion and Hurrion (2008) observed similar results, with the amateur group recording CP excursion of 12.23mm in the downswing in comparison to the professional groups 10.13mm, this however was not found to be significant. Delphinus and Sayers (2012) did not directly measure the CP however measured the movement of the centre of mass (CM), which has a direct relationship with the CP in proficient and non-proficient golfers. It was identified that proficient golfers moved predominantly in the frontal plane in comparison to the non-proficient golfers where more sagittal movements were recorded (Delphinus and Sayers, 2012). Additionally Delphinus and Sayers (2012) found non-proficient golfers demonstrated increased movement variability in comparison to the proficient golfers, which may go some way to explain the increased CP excursions observed for less proficient groups in Hurrion and Hurrion (2008) and McLaughlin et al. (2008).

McLaughlin et al. (2008) suggests that a LH group is more able to optimise the movement of CP excursions when compared to the MH and HH groups. During the downswing the HH had a max velocity of 64.5  48 mms-1 in comparison to 29.7  25 mms-1 for the LH group and 39.8  36.3 mms-1, the LH was found to be significantly less (p < .001) than the HH group. A trend was identified where the higher a player’s handicap was the greater values in max velocity and average velocity during the downswing were observed. Delay et al. (1997) observed that when the distance of a putt was increased subjects increased the DS amplitude while maintaining the DS movement time; this is an increase in velocity in accordance with McLaughlin et al. (2008). Karlsen et al. (2008) found some indication that long DS times have a negative effect on consistency for some players; this may be due the players consciously controlling the motion. Velocity was not reported by Karlsen et al. (2008) however it seems to be of an opposite opinion to McLaughlin et al. (2008), however it may be only extremely long DS times that have a negative effect on the putting stroke. Karlsen et al. (2008) suggests that DS times between 270 and 370 msec produced the best overall performance. Delay et al. (1997) reported longer DS times for novice (584 msec) and expert golfers (719 msec) however this was due to different definitions of DS, Karlsen et al. (2008) DS phase ended at Impact, whereas Delay et al. (1997) DS phase ended at the highest position of the club after contact with the ball. However it should be noted that expert golfers demonstrated a longer DS time in accordance with McLaughlin et al. (2008)

Karlsen et al. (2008) take a different standpoint concerning the putting stroke; arguing the fact the putting stroke only has a minor contribution to the overall success of a putt. Karlsen et al. (2008)

found mean stroke direction variability for an elite player (European PGA Tour) to be 0.39, which is good enough to hole 95% of putts from a 4-metre distance, whereas only 17% of putts from this distance are successful. Pelz, (2000) makes the assumption that 30% of putts from 4-metres are missed due to green inconsistencies, Karlsen et al. (2008) findings support this fact, along with human controlled factors green reading and aiming have a stronger contribution to the direction of a putt, than the stroke itself. Pelz, (2000) also describes numerous factors that contribute to a successful putting stroke, which green-reading and aim are included, recently reported by Karlsen et al. (2008) reported as the most important factors; and stability more recently discussed by Hurrion and Hurrion, (2008). Low handicap golfers (<14) have the ability to combine these factors together to become more proficient putters, making putts less than 2.43 metres much more often than their HH counterparts (Carnahan, 2002). It was also reported by Carnahan (2002) that the incidence of three-putts within 3.66 metres was 2.1%; for subjects with a handicap of <14 the occurrence was 1.2%, and for subjects with a handicap that was > 14 the occurrence was 3.8%. This was found to be statistically significant (p = 0.008).

More recently McLaughlin and Best (2013) have critiqued previous studies for grouping golfers based on putting performance or handicap. McLaughlin and Best (2013) identified two styles of putter, firstly the arm putter that demonstrates a low CP excursion velocity at impact (5.2 ± 16.9 mms-1) and a body putter that demonstrates a higher ML CP excursion velocity at impact (58.4 ± 22.9 mms-1). These different styles of putter were identified using cluster analysis and ML CP excursion velocity at impact was the highest ranked cluster between types of putter. A potential limitation to McLaughlin and Best (2013) is that no kinematic variables of actual body movements were recorded, and therefore different types of putters may have just been using different movement patterns. It is possible that the arm putters move in a way that reduces the CP excursion but doesn’t in fact move less that the body putters. The lack of clarity in this area still gives studies by Hurrion and Hurrion (2008) and McLaughlin et al. (2008) validity within the literature. As both studies found significant differences were observed between more proficient golfers and less proficient golfers CP excursion parameters, even if McLaughlin and Best (2013) did not find significant differences. A potential reason for these differences observed between studies could be the large inter-subject variation observed. McLaughlin and Best (2013) even stated that half of the subjects actually interchanged between the arm putting and body putting style.