Gianfranco Ibba

The acute effect of whole body vibration on repeated shuttle-running in young soccer players.

The aim of this study was to investigate the acute effects of whole-body vibration (WBV) on Repeated Sprint Ability (RSA). Seventeen male soccer players (16.71±0.47 y) performed three RSA tests (Randomized crossover study design). The second RSA test was done with WBV (RSA2) to assess the effect of WBV. The studied variables were: best time (BT), worst time (WT), total time (TT), the fatigue index (FI) of RSA, and post-test blood lactate (BLa). ANOVA with repeated measures showed no differences between RSA1 and RSA3, while there were significant differences in all variables studied. TT= [RSA2 0.93% and 1.68% lower than RSA1 and RSA3 respectively; p<0.05], BLa= [RSA2 16.97% and 14.73% greater than RSA1 and RSA3 respectively; p<0.001], WT= [RSA2 1.90% and 2.93% lower than RSA1 and RSA3 respectively; p<0.01], and FI = [RSA2 30.64% and 40.15% lower than RSA1 and RSA3 respectively; p<0.0001]. When comparing individual sprints, WBV showed a significant effect at the 5th sprint: RSA2 2.29% and 2.95% lower than RSA1 and RSA3 respectively (p<0.005), while at the 6th sprint: RSA2 2.75% and 4.09% lower than RSA1 and RSA3 respectively; p<0.005. In conclusion, when applying WBV during the recovery periods of Repeated Sprint Ability efforts, most of the performance variables improved.

Fatigue-Induced Balance Impairment in Young Soccer Players

CONTEXT Although balance is generally recognized to be an important feature in ensuring good performance in soccer, its link with functional performance remains mostly unexplored, especially in young athletes. OBJECTIVE To investigate changes in balance induced by fatigue for unipedal and bipedal static stances in young soccer players. DESIGN Crossover study. SETTING Biomechanics laboratory and outdoor soccer field. PATIENTS OR OTHER PARTICIPANTS Twenty-one male soccer players (age = 14.5 ± 0.2 years, height = 164.5 ± 5.6 cm, mass = 56.8 ± 6.8 kg). INTERVENTION(S) Static balance was assessed with postural-sway analysis in unipedal and bipedal upright stance before and after a fatigue protocol consisting of a repeated sprint ability (RSA) test (2 × 15-m shuttle sprint interspersed with 20 seconds of passive recovery, repeated 6 times). MAIN OUTCOME MEASURE(S) On the basis of the center-of-pressure (COP) time series acquired during the experimental tests, we measured sway area, COP path length, and COP maximum displacement and velocity in the anteroposterior and mediolateral directions. RESULTS Fatigue increased all sway values in bipedal stance and all values except COP velocity in the mediolateral direction in unipedal stance. Fatigue index (calculated on the basis of RSA performance) was positively correlated with fatigue/rest sway ratio for COP path length and COP velocity in the anteroposterior and mediolateral directions for nondominant single-legged stance. CONCLUSIONS Fatigued players exhibited reduced performance of the postural-control system. Participants with better performance in the RSA test appeared less affected by balance impairment, especially in single-legged stance.

Relationship between static and dynamic balance abilities in Italian professional and youth league soccer players

OBJECTIVES To assess the existence of correlations between static and dynamic balance abilities in young and professional elite soccer players. DESIGN Cross-sectional. PARTICIPANTS Fifty-one elite players who regularly compete at national level divided into two groups: Professional (age 18-34, n = 20) and Under 15-17 (age 14-16, n = 31). MAIN OUTCOME MEASURES Dynamic balance was assessed for the case of a single-leg landing task by means of vertical time to stabilization (TTS) and postural sway calculated on the basis of center-of-pressure (COP) trajectories (sway area, COP displacements in antero-posterior and medio-lateral direction, COP path length). The same parameters were also measured for a 20 s one-legged stance to assess static balance abilities. RESULTS No significant correlations were found between static and dynamic balance parameters except for TTS and COP displacements in the antero-posterior direction (r = 0.29, p = 0.003). Professional players are characterized by lower TTS in comparison with youth leagues players (0.767 vs. 1.188 s for the dominant limb, p < 0.001) and exhibit reduced sway area (of 34-40%, p < 0.05) for both conditions tested. CONCLUSION The assessment of balance in soccer players should be performed with both dynamic and static tests, considering that the postural control performances in the two cases are not related.

Characterization of Static Balance Abilities in Elite Soccer Players by Playing Position and Age

In this study, we investigated the static balance of adult and adolescent elite soccer players to understand how expertise and playing position influence postural control. Seventy-one national level players were tested using a force platform to acquire Center-of-Pressure (COP) data in uni- and bipedal stance and calculate sway area (SA), COP path length, velocity and displacements. The results show significant differences in postural sway related to age and playing position only for single-limb stance. In particular, midfielders exhibited significantly lower values of SA with respect to defenders (–48%, p = 0.001) and the under-15 players exhibited SA 42–64% higher than all the others (p = 0.001). In the light of planning training or rehabilitation programs specific for each player’s role and age, sway measurements may supply useful, objective and reliable information only for the unipedal test as the bipedal standing appears not challenging enough to let differences in balance abilities emerge.

Indexes of physical capacity and repeated sprint ability of young soccer players

Repeated sprint ability (RSA) is thought to be an important skill for team sports. However, there is no study that correlates aerobic capacity (AC) and lactic anaerobic capacity (LAC) with RSA in young elite soccer players. Fourteen young players from a professional soccer team underwent two laboratory tests: an incremental exercise test (IET) and an all-out test (AOT) to asses AC and LAC, respectively. Athletes also performed a field RSA test. During both the IET and the AOT tests heart rate, oxygen uptake, carbon dioxide production, and pulmonary ventilation were obtained by a portable gas analyzer. Velocity and fatigue indices were measured during the RSA test. Blood lactate was also measured after the AOT (BLaAOT) and the RSA (BLaRSA) test. No correlation was found between AC and LAC indices and measures of the RSA test, even though the AOT test appeared to fully recruit LAC capacity, as no difference between BLaAOT and BLaRSA was detected. It was concluded that no correlation exists between AC and LAC capacities obtained in the laboratory setting and velocity and fatigue measures from RSA testing. This finding should be taken into account when testing young soccer players.

A 12-Week Vigorous Exercise Protocol in a Healthy Group of Persons over 65: Study of Physical Function by means of the Senior Fitness Test

The aim of this study was to assess the effects of vigorous exercise on functional abilities by means of a Senior Fitness Test (SFT) in a group of elderly adults. Twenty healthy and inactive people performed vigorous exercise (VE: 12 men and 8 women, aged 69.6 ± 3.9 years). At the beginning of the study (T0) and after 3 months (T1), each subjects functional ability was tested for muscular strength, agility, cardiovascular fitness, flexibility, and balance. The VE was designed with continuous and interval exercise involving large muscle activities. Functional exercises were performed between 60% and 84% of heart rate reserve (HRR) for a duration of 65 minutes. Five out of the 6 SFTs performed were found significantly improved: Chair Stand (T0 12.4 ± 2.4, T1 13.5 ± 2.6, p < 0.01), Arm Curl (T0 14.2 ± 3.6, T1 16.6 ± 3.6, p < 0.01), 2 min step (T0 98.2 ± 15.7, T1 108.9 ± 16.2, p < 0.01), Chair Sit-and-Reach (T0 −9.9 ± 7.7 cm, T1 1.7 ± 6.3 cm, p < 0.01), and Back Scratch (T0 −15.8 ± 10.9 cm, T1 −8.4 ± 13.1 cm, p < 0.01). Our results suggest that a high intensity protocol and functional exercises can improve functional mobility and muscle endurance in those over 65 years of age. SFTs are an effective method for assessing improvements in the functional capacity of elderly adults.