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Capítulo II. El turismo y el patrimonio en la construcción de Valparaíso

2.1 El Turismo en Chile: breve revisión histórica

2.1.2 El papel de Chile en el turismo internacional

and 3.8 of Grieve and Pheasant (1982) respectively 44

Figure 2.2: Figure 7 from Perrine and Edgerton (1978) (redrawn) showing force- velocity relationships of isolated animal and in-vivo human muscles determined under similar loading conditions. Open circles are data obtained from isolated animal muscles by Hill (1970). Closed circles are data obtained by Perrine and Edgerton (1978) from in-vivo human muscle scaled to yield the best-fit with the isolated muscle curve. 46 Figure 2.3: The power-velocity curve, redrawn from Fig 3.9 of Grieve and

Pheasant (1982) 47

Figure 2.4: Figure 6 from Perrine and Edgerton (redrawn). Power-velocity curve obtained from 15 subjects, showing means and ranges of power

normalised to maximum power. 47

Figure 2.5: Figure 1 from Stevenson era/. (1996a). Original legend: "A schematic diagram of the incremental lifting machine (ILM). The cutaway shows the ball bearing rollers. Also, the barrier has been removed to expose

the stack of weights." 52

Figure 2.6: Figure 2 from Stevenson et al (1996a) (redrawn) with event numbers added from Stevenson e ta l (1990a). Original legend: "Dynamic measures of an ILM lift for one subject. All four curves have the same abcissa with scales in seconds and in percentage of lift cycle.

Maximum and minimum values have been identified on the curves

representing displacement, velocity, force/acceleration and power." 57 Figure 2.7: Figure 2 from Weisman et a l (1990b). Original legend: "Typical plot

of force vs. height data for full lift and segmented lift at HDl"

(HDl = 30% of arm length) 59

Figure 2.8: Figure 3 from Weisman et a l (1990b). Original legend: "Typical plot of force vs height data for full lift and segmented lift at HD4."

(HD4 = 90% of arm length) 60

Figure 2.9: Fig. 1 from Weisman e ta l (1992) (redrawn). Original legend: "Plotted data from a single subject, lifting at one speed. Horizontal distances (HD) 1 through 4 represent 30%, 50%, 70%, and 90% of arm

length respectively." 61

Figure 2.10: Fig. 2 from Weisman et al (1992) (redrawn). Original legend: "Strength, throughout a range of motion and at different horizontal distances (reach), is depicted with contour lines for a single subject. The resulting pattern of iso-strength lines varied little from subject to

Figure 2.11: Fig. 4 from Weisman et a l ( 1992) (redrawn). Original legend: "The bars show the area from plus one to minus one standard deviations in lifting force generated at each of four horizontal distances from the body. The data for both slow lifts and fast lifts are illustrated. In general, there is little effect of horizontal distance (determined as percent of arm length) on force at either middle level or high lifts, regardless of whether the lifts are fast or slow. However, at low heights, there is a more dramatic decrease in generated force, as

horizontal distance increases." 62

Figure 2.12: Fig. 1 from Chaffin (1974) (redrawn) 62

Figure 2.13: Schematic diagram of the Super Mini-Gym device. Derived from

Figure 1 of Pytel and Kamon (1981) / Kamon et a l (1982) 63 Figure 2.14:Figures 2 and 3 from Garg et a l (1988) (combined): Variation with

time of dynamic pulling strength and velocity of pull for typical male

(---) and female (— ) pulls 68

Figure 2.15:Fig.3 from Bosco et al (1995) (redrawn). According to the original legend: "Average force (F) (squares) and average power (P) (dots), developed during half-squat exercises performed with various loads (from 35% to 210% of the subject's body mass) are shown according to the average vertical velocity (V) for male (filled symbols) and female

(open symbols) jumpers." 75

Figure 2.16:Fig. 4 from Bosco e ta l (1995) (redrawn). Original legend: "Power ratio (men : women in percentages) found in half-squat exercise according to the loads used (from 35% to 210% of the subject's body

mass, n = 7)." 75

Figure 3.1: Vertical section on plane A-A' and plan view of the hydrodynamometer, showing important dimensions. H is the handle grasped by the subject; P is the piston assembly; (both H and P are shown in their resting positions); PI - P4 are pulleys the wire rope, WR, passes around; C is the cantilever; G is the site of the strain gauges; FI is the footline marked beneath the handle; SP is the splash plate at the top of the tube. The tube is filled with water to within a few centimetres of the splash

plate 88

Figure 3.2: Exploded isometric view of the piston assembly (total mass 5.85 kg). The lead collar (4.55 kg) slides down the central pillar and rests against the legs of the spider. The piston rests against the shoulder at the top of the pillar and the nut is screwed down to hold it. A bolt holds the steel plates to the cheeks at the top of the pillar and a bolt through the top of the top of the plates passes through an eye in the end of the wire rope 89

Figure 3.3a: Diagram showing the relationship between vectors of the force in the rope, Fh, and the resultant force, F(^, on the cantilever. 0 is the angle

between the rope and the vertical 90

Figure 3.3b:Diagram showing how 0 changes when the cantilever is loaded with the force F^. The point of application of F^ deflects vertically by a

distance Ah, resulting in the angle 0 changing to 0. 1 and h represent the physical dimensions between the point where the rope leaves pulley

PI and makes contact with pulley P2 90

Figure 3.4: Possible combinations of output from the shaft encoder showing how sequences of changes of state (’edges') differ during lifting and

lowering 91

Figure 3.5: Relationship between the force in the rope and the errors that would

occur if no correction was made for the deformation of the cantilever 92 Figure 3.6: Example of the time histories, from the start of movement, of the

handle height, force in the rope, velocity of pull, and power output

produced during one pull 95

Figure 3.7: Scatter plot, mean regression line, 95% confidence limits for the mean and 95% confidence limits for the predictions obtained from a

regression of Fy against V using a multiplicative model of the form Ffj = a-V^. Values of F^ and V were obtained at points of zero

acceleration from a total of 228 exertions over a range from 0.4 m to at

least 1.8 m carried out by 78 subjects 96

Figure 3.8: Plots of linear regressions of the form F^ = c - c a l c u l a t e d for eight different numbers of holes in the piston. Values of F^ and V were obtained at points of zero acceleration from three pulls carried out in

each condition by a single subject 97

Figure 4.1 : Screen grab of display showing displacement, force, velocity and

power, with times and magnitudes of 'Events' identified 107

Figure 5.1: Mean powers ± 1 standard deviation for males and females at hand heights of 0.7, 1.0, 1.45 and 1.7 m (Events 1-4) and Events 19-25.

Mean hand heights ± 1 standard deviation are shown for Events 19-25 113 Figure 5.2: Regression of power between 0.7 m and 1.0 m on power between 0.7 m

and 1.45 m 117

Figure 5.3: Regression of power between 0.7 m and 1.0 m on power between 0.7 m

and 1.7 m 118

Figure 5.4: Regression of power below the first grip change on power between the

two grip changes 119

Figure 5.5: Regression of power below the first grip change on power between the

Figure 5.6: Regression of power below the first grip change on power between the

second grip change and 1.7 m 121

Figure 5.7: Mean powers, with 95% Tukey HSD intervals, between 0.7 m and

1.0 m of Groups B, C and D 123

Figure 5.8: Means and 95% Tukey HSD intervals of stature and body mass of male

subjects. 126

Figure 5.9: Means and 95% Tukey HSD intervals of fat free mass and isometric

lifting strength at 850 mm of male subjects. 126

Figure 5.10: Regression of work done on the ILM to 1.45 m on work done on the

hydrodynamometer to 1.45 m 129

Figure 5.11: Regression of work done on the ILM to 1.7 m on work done on the

hydrodynamometer to 1.7 m. a = males; “h = females 130

Figure 5.12: Regression of work done in a maximal box lift to 1.45 m on work done

on the hydrodynamometer to 1.45 m 132

Figure 5.13:Regression of work done in a maximal box lift to 1.7 m on work done

on the hydrodynamometer to 1.7 m 133

Figure 5.14: Regression of height of main power peak on subject stature 134 Figure 6.1 : Effect of the choice of the first covariate to enter the model, for

absolute hand heights 150

Figure 6.2: Effect of the choice of the second covariate to enter the model, for

absolute hand heights 150

Figure 6.3: Effect of the choice of the first covariate to enter the model, for relative

hand heights 151

Figure 6.4: Effect of the choice of the second covariate to enter the model for

relative hand heights 151

Figure 6.5: Variance in instantaneous power accounted for by gender, with and without the removal of the effects of covariates, for absolute hand

heights 152

Figure 6.6: Variance in instantaneous power accounted for by gender, with and without the removal of the effects of covariates, for relative hand

heights 153

Figure 6.7: Effect of gender and absolute hand height on force produced 154 Figure 6.8: Effect of gender and relative hand height on force produced 154 Figure 6.9: Effect of gender and absolute hand height on power produced 155 Figure 6.10: Variance of power output accounted for by gender and three covariates

at absolute hand heights with significance levels of gender after

correction for covariates 156

Figure 6.11: Effect of gender and relative hand height on power produced 157 Figure 6.12: Variance of power output accounted for by gender and three covariates

at relative hand heights with significance levels of gender after

correction for covariates 158

Figure 6.13: Effect of gender and absolute hand height on work done 159

Figure 6.14: Variance in work done accounted for by gender and three covariates for absolute hand heights with significance levels of gender after correction

for covariates 160

Figure 6.15: Effect of gender and relative hand height on work done 161

Figure 6.16: Variation in work done accounted for by gender and three covariates for relative hand heights with significance levels of gender after correction

for covariates 162

Figure 6.17:Effect of gender and absolute hand height on impulse 164

Figure 6.18: Variance in impulse accounted for by gender and three covariates for absolute hand heights with significance levels of gender after correction

for covariates 165

Figure 6.19: Effect of gender and relative hand height on impulse 166

Figure 6.20: Variance in impulse accounted for by gender and three covariates for relative hand heights with significance levels of gender after correction

for covariates 167

Figure 6.21:Female : male ratios for force at absolute hand heights 168 Figure 6.22:Female : male ratios for power at absolute hand heights 168 Figure 6.23: Female : male ratios for work done to absolute hand heights 169 Figure 6.24: Female : male ratios for impulse to absolute hand heights 169 Figure 6.25: Female : male ratios for force at relative hand heights 170 Figure 6.26: Female : male ratios for power at relative hand heights 170 Figure 6.27: Female : male ratios for work done to relative hand heights 171 Figure 6.28: Female : male ratios for impulse to relative hand heights 171

CHAPTER 1