Acute effects of static and dynamic stretching on jump performance after 15 min of reconditioning shooting phase in basketball players

2016-09-15. Effects of long term stimulation of textured insoles on postural control in health elderly. In JOURNAL OF SPORTS MEDICINE AND PHYSICAL FITNESS - ISSN:0022-4707 Annino, G; Palazzo, F; Alwardat, M; Manzi, V; Lebone, P; Tancredi, V; Sinibaldi Salimei, P; Caronti... Resp. del dato : GIUSEPPE ANNINO Identificativo : hdl:2108/164271 01 - Articolo su rivista validato errore 10/11/2016 12:37 Sito docente: Success

Effects of stimulating surface during static upright posture in the elderly

This study aimed to investigate the influence of three stimulating surfaces based on center of pressure (CoP), anteroposterior sway velocity (VA/P), and medio-lateral sway velocity (VM/L) of 40 elderly subjects. CoP and VM/L showed a significant decrease in all visual conditions only in the stimulating surface whereas VA/P showed a significant decrease only on the same surface with eyes open. Results confirm the importance of multisensory stimulation in postural control in the elderly

The efficacy of plantar stimulation on human balance control

Aim: The aim of this study was to evaluate the body sway using firm, foam, and firm textured surfaces on 17 young adults. Method: Displacement of center of pressure (CoP), anteroposterior velocity (VA/P), and mediolateral velocity (VM/L) were measured. Data: The data showed a significant decrease of CoP, VA/P, and VM/L between support surfaces and vision. Results: The results showed that, differently from the firm and foam, the textured surface is able to increase the plantar feedback to maintaining postural control

Slopes And Speed Related Effects On Kinematic And Emg Patterns In Elite Race Walking.

Introduction. In human locomotion every external condition generates a strategy. The aim of this study is to analyze the kinematics parameters and to indentify the changes in movement pattern and muscle activity of race-walkers (RW). Methods. Twelve elite RW have race walking on a treadmill for 5 minutes each slope (0, 2 and 7%) in iso-efficiency speed (IES1) with heart rate and sEMG on leg muscles constantly monitored. Digital cameras (210 Hz) were used to record; Dartfish 5.5Pro was used to perform a 2D video analysis, while for statistical analysis was used Anova. (1) The IES (km/h) for each subject at 0% grade was the average speed during the best performance in the 10000 m race, minus 1 km/h, which corresponds to the ~50% Vo2MAX and requires an energy cost (Cw0) of 5.0 J/m/kg according to previous studies (Di Prampero 1986). Moreover, according to previous data (Minetti et al. 2002) the increase of Cw as a function of ground slope is: 0.15 * slope (%) + Cw0. We calculated for each ground slope the IES at which the Vo2 was equal to the oxygen consumption during level race walking using the following equation: Vo2= (Cw0/21(J/m) * (IES0/0.06 (m/min)) IES= (Vo2 * 21 * 0.06)/(0.15(Cw) * slope (%) + (Cw0)) Results IES, step length (SL) and frequency (SF) decrease as a function of the increasing slope: IES0 12.5 \u2013 IES2 11.8 \u2013 IES7 10.3; SL= (0-2%= -3.71%, n.s.; 0-7%= -12.23%, p<0.001); SF= (0-2%= -2.38%, n.s.; 0-7%= -6.07%, p<0.01). The contact time (CT) and heart rate (HR) increase at the increasing slope: CT= (0-2%= 2.46%, n.s.; 0-7%= 6.56%, p<0.01); HR= (0-2%= 0.62%, n.s.; 0-7%= 3.25%, p<0.05). The sEMG activity was reduced at the increasing slope in: tibialis anterior (0-2%= 22.49%, p<0.0001; 0-7%= 41.18%, p<0.0001); rectus femoris (0-2%= 15.35%, p<0.0001; 0-7%= 29.13%, p<0.0001). While the sEMG activity was increased in this muscles: vastus lateralis (0-2%= 22.95%, p<0.0001; 0-7%= 31.15%, p<0.0001); gastrocnemius medialis (0-2%= 21.40%, p<0.001; 0-7%= 48.37%, p<0.0001); biceps femoris (0-2%= 190.78%, p<0.0001; 0-7%= 201.37%, p<0.0001). Discussion. These results provide the resultant of the real mechanical work in different slopes without increasing energetic cost, validating the equation to calculate the speed in RW only at IES between zero and 2% gradient. While for higher gradient levels the procedure used in this study seems to overestimate the speed, probably due to the different biomechanics between walking (Minetti et al., 2002) and race walking. References Di Prampero PE. The energy cost of human locomotion on land and in water. (1986). Int J Sports Med, 7 (2), 55-72. Minetti AE, Moia C, Roi GS, Susta D, Ferretti G. Energy cost of walking and running at extreme uphill and downhill slopes. (2002). J Appl Physiol, 93(3),1039-1046

Acute effects of static and dynamic stretching on jump performance after 15 min of reconditioning shooting phase in basketball players

BACKGROUND: The aim of this study was to assess the effects of static (SS) and dynamic stretching (DS) on vertical jump performance executed before, immediately after and at the end of the shooting phase (i.e., 15 min later), as to simulate the actual conditions preceding a match, in professional basketball players. METHODS: Ten elite basketball players (age: 29±6.73 years, height: 194.67±7.75 cm, weight: 91±8.17 kg and BMI 23.8±7.91 kg.m-2) participated to the study. SS and DS protocols were administered during the first training session of the week, 48 hours after the championship match. Stretching protocols consisted in ∼7 minutes of general warm-up phase followed by ∼8 minutes of SS and DS, performed with a cross-over design., and ∼15 minutes of a specific warm-up shooting phase (SP). Vertical jump tests consisted in counter movement jump (CMJ) and CMJ with arm swings (CMJas) and were performed immediately after the end of each stretching phase (preS, posts, postSP). RESULTS: A significant decrease (P=0.05; η2partial=0.29) in jumping tests height occurred in CMJas, when performed after the SS (i.e., PostS). However, no significant differences in jumping performances, occurred after the general warm phase and the specific warm-up shooting phase, between the two stretching protocols. CONCLUSIONS: These results would indicate that, overall, stretching routines either dynamic or static, performed before a basketball match are transient and affect only marginally leg muscles performance. Stretching routines, particularly the dynamic ones, may be useful to maintain muscle performance before a competition, provided that this latter begins shortly after

Effects of long term stimulation of textured insoles on postural control in health elderly

Background: The aim of this study was to confirm the effects of long term (chronic) stimulating surface (textured insole) on body balance of elderly people. Methods: Twenty-four healthy elderly individuals were randomly distributed in two groups: control and experimental (67.75 ± 6.04 yrs, 74.55±12.14 kg, 163.7 ± 8.55 cm, 27.75 ± 3.04 kg/m2). Over one month, Control Group (CG) used smooth insoles and the Experimental Group (ExG) used textured insoles every day. Velocity net (Vnet), anteroposterior (VA/P), mediolateral (VM/L) and sway path of CoP were assessed in different eye conditions before and after the experimental procedure. Results: A mixed between-within subject ANOVA was conducted to assess the impact of soft and textured insoles and two visual conditions (vision vs no vision) across two time periods (α ≤ 0.05). The results showed any statistical difference between groups in each parameter assessed in this study. CoP, Vnet and VM/L in the experimental group showed a statistically significant effect of textured insoles only without vision (CoP: P= 0.002; η2=0.35), Vnet P=0.02; η2=0.24, VM/L P=0.04; η2=0.177) whereas VA/P showed no statistically significant effect in the same group and condition. There was no significant effect in Vnet, VA/P, VM/L and COP in control group that used smooth insole for both eye conditions. Conclusions: The results confirm that postural stability improved in healthy elderly individuals, increasing somatosensory information's from feet plantar mechanoreceptors. Long term stimulation with textured insoles decreased CoP, Vnet and VM/L with eyes closed

Slopes and speed related effects on kinematic and EMG patterns in elite race walking

Introduction. In human locomotion every external condition generates a strategy. The aim of this study is to analyze the kinematics parameters and to indentify the changes in movement pattern and muscle activity of race-walkers (RW). Methods. Twelve elite RW have race walking on a treadmill for 5 minutes each slope (0, 2 and 7%) in iso-efficiency speed (IES1) with heart rate and sEMG on leg muscles constantly monitored. Digital cameras (210 Hz) were used to record; Dartfish 5.5Pro was used to perform a 2D video analysis, while for statistical analysis was used Anova. (1) The IES (km/h) for each subject at 0% grade was the average speed during the best performance in the 10000 m race, minus 1 km/h, which corresponds to the ~50% Vo2MAX and requires an energy cost (Cw0) of 5.0 J/m/kg according to previous studies (Di Prampero 1986). Moreover, according to previous data (Minetti et al. 2002) the increase of Cw as a function of ground slope is: 0.15 * slope (%) + Cw0. We calculated for each ground slope the IES at which the Vo2 was equal to the oxygen consumption during level race walking using the following equation: Vo2= (Cw0/21(J/m) * (IES0/0.06 (m/min)) IES= (Vo2 * 21 * 0.06)/(0.15(Cw) * slope (%) + (Cw0)) Results IES, step length (SL) and frequency (SF) decrease as a function of the increasing slope: IES0 12.5 \u2013 IES2 11.8 \u2013 IES7 10.3; SL= (0-2%= -3.71%, n.s.; 0-7%= -12.23%, p<0.001); SF= (0-2%= -2.38%, n.s.; 0-7%= -6.07%, p<0.01). The contact time (CT) and heart rate (HR) increase at the increasing slope: CT= (0-2%= 2.46%, n.s.; 0-7%= 6.56%, p<0.01); HR= (0-2%= 0.62%, n.s.; 0-7%= 3.25%, p<0.05). The sEMG activity was reduced at the increasing slope in: tibialis anterior (0-2%= 22.49%, p<0.0001; 0-7%= 41.18%, p<0.0001); rectus femoris (0-2%= 15.35%, p<0.0001; 0-7%= 29.13%, p<0.0001). While the sEMG activity was increased in this muscles: vastus lateralis (0-2%= 22.95%, p<0.0001; 0-7%= 31.15%, p<0.0001); gastrocnemius medialis (0-2%= 21.40%, p<0.001; 0-7%= 48.37%, p<0.0001); biceps femoris (0-2%= 190.78%, p<0.0001; 0-7%= 201.37%, p<0.0001). Discussion. These results provide the resultant of the real mechanical work in different slopes without increasing energetic cost, validating the equation to calculate the speed in RW only at IES between zero and 2% gradient. While for higher gradient levels the procedure used in this study seems to overestimate the speed, probably due to the different biomechanics between walking (Minetti et al., 2002) and race walking. References Di Prampero PE. The energy cost of human locomotion on land and in water. (1986). Int J Sports Med, 7 (2), 55-72. Minetti AE, Moia C, Roi GS, Susta D, Ferretti G. Energy cost of walking and running at extreme uphill and downhill slopes. (2002). J Appl Physiol, 93(3),1039-1046

Effect of textured insoles on postural control during static upright posture following lower limb muscle fatigue

The purpose of this study was to assess the effects of textured insoles on static upright posture before and after lower limb muscle fatigue. Textured insoles used contained small and non-deformable pebbles of various sizes that are able to stimulate a major number of mechanoreceptors. It was inserted inside footwear