Time-motion characteristics and physiological responses of small-sided games in elite youth players: The influence of player number and rule changes

The aim of this study was to examine acute physiological responses and time-motion characteristics associated with 4 soccer-specific small-sided game (SSG) formats (3 vs. 4 players, 3 vs. 3 players + floater, 5 vs. 6 players, and 5 vs. 5 players + floater) and 4 rule changes in elite youth soccer players. Sixteen male youth soccer players (mean ± SD: age = 15.6 ± 0.8 years, stature = 170.8 ± 6.6 cm, body mass = 67.5 ± 6.2 kg, and 20-m shuttle run estimated V̇2 max = 57.4 ± 3.7 ml·kg-1-min-1) participated in the study, in which heart rate (HR), rating of perceived exertion (RPE), blood lactate (La -), and time-motion characteristics were recorded. The rule change requiring extra sprint running had a greater effect on the time-motion characteristics than all other rule modifications but no effect on acute %HRmax, La-, and RPE. Rule changes had no effect on RPE. Fixed underload teams (i.e., lower number of players compared with the opponent team) recorded a significantly higher RPE compared with the fixed overload teams, although there were no differences in %HRmax and La-. The major practical findings are that subtle changes in SSGs playing rules can influence the physiological, perceptual, and time-motion responses in young elite soccer players. Rules that are related to a team's chances of scoring may improve player motivation and thereby increase training intensity during SSGs. There were no differences between fixed and variable formats in terms of physiological and perceptual responses, although both may provide useful technical-tactical training. Coaches should take care in designing different soccer SSGs as each rule or game format change may influence exercise intensity independently. © 2010 National Strength and Conditioning Association

Generic versus small-sided game training in soccer

The aim of this study was to compare 7 weeks of soccer-specific small-sided game (SSG) and mixed generic fitness training, on selected physiological, perceptual and performance variables. Twenty-five elite youth players were randomly allocated to either a SSG (coach selected) or generic training group (GTG), in a randomised, parallel matched-group design. In addition to normal training, each group completed two fitness training sessions per week of equal duration. Players completed a VO2max treadmill test, Multistage Fitness Test (MSFT), Yo-Yo Intermittent Recovery Test Level 1 (YYIRTL1), 12 20m test of repeated-sprint ability (RSA) and 20-m sprint test pre and post training. Training heart rate, perceived training intensity and perceptual fatigue measures were recorded throughout the training period. There were no differences in training heart rate or perceptual well-being measures. However, the GTG did perceive their training to be more intense than SSG. There were no changes in either group for VO2max, MSFT, RSA or sprint performance. However, there were improvements in YYIRTL1 performance for both groups over time, but not between groups. The results show that both types of training are equally effective at improving pre-season YYIRTL1 performance, despite GTG being perceived to be more intense

Acute physiological responses and timemotion characteristics of two small-sided training regimes in youth soccer players

Hill-Haas, SV, Rowsell, GJ, Dawson, BT, and Coutts, AJ. Acute physiological responses and time-motion characteristics of two small-sided training regimes in youth soccer players. J Strength Cond Res 23(1): 111-115, 2009-The purpose of this study was to examine the acute physiological responses and timemotion characteristics associated with continuous and intermittent small-sided games (SSGs). The continuous (SSGC) regime involved 24 minutes' playing duration (no planned rest intervals), whereas the intermittent regime (SSGI) involved 4 × 6-minute bouts with 1.5 minutes of passive planned rest (work:rest ratio 4:1). Both training regimes were implemented across 3 SSG formats, which included games with 2 vs. 2, 4 vs. 4, and 6 vs. 6 players. Sixteen men's soccer players (mean ± SE: age = 16.2 ± 0.2 years, height = 173.7 ± 2.1 cm, body mass = 65.0 ± 2.5 kg, estimated Vo2max = 54.8 ± 0.7 ml·kg-1·min-1) participated in the study. Heart rate (HR) was measured every 5 seconds during all SSGs. Global ratings of perceived exertion (RPEs) were recorded immediately after the SSGs using the Borg scale (RPEs, 6-20). Capillary blood samples were drawn at rest and within 5 minutes after the end of each SSG. Time-motion characteristics were measured using portable global positioning system units. There were no significant differences between SSGC and SSG I for total distance covered or for distance traveled while walking, jogging, or running at moderate speed. However, players covered a significantly greater distance at 13.0-17.9 km·h-1, a greater total distance at higher running speed, and a greater total number of sprints (>18 km·h-1) with SSGI compared with SSGC. In contrast, global RPE and %HRmax were significantly higher in SSGC than in SSGI. Both intermittent and continuous SSG training regimes could be used during the season for match-specific aerobic conditioning. However, both training regimes used in this study seem unlikely to provide a sufficient stimulus overload for fully developing Vo2max. © 2009 National Strength and Conditioning Association

Effect of post-match cold-water immersion on subsequent match running performance in junior soccer players during tournament play

In this study, we investigated the effects of two hydrotherapy interventions on match running performance and perceptual measures of fatigue and recovery during a 4-day soccer tournament. Twenty male junior soccer players were assigned to one of two treatment groups and undertook either cold-water immersion (5 × 1 min at 10°C) or thermoneutral water immersion (5 × 1 min at 34°C) after each match. High-intensity running distance (> 15 km · h-1) and total distance covered, time spent in low (90% maximum heart rate) heart rate zones, and rating of perceived exertion (RPE) were recorded for each match. Perceptions of general fatigue and leg soreness were recorded approximately 22 h after each match. There were decreases in both groups across the 4-day tournament for high-intensity running distance (P=0.006, Cohen's d=0.63), total distance run (P < 0.001, d=0.90), time in high heart rate zone (P=0.003, d=0.90), and match RPE (P=0.012, d=0.52). Cold-water immersion was more effective than thermoneutral immersion for reducing the perception of leg soreness (P=0.004, d=-0.92) and general fatigue (P=0.007, d=-0.91), ameliorating the decrement in total distance run (P=0.001, d=0.55), and maintaining time in the moderate heart rate zone (P=0.01, d=1.06). In conclusion, cold-water immersion mediates the perceptions of fatigue and recovery and enhances the restoration of some match-related performance measures during a 4-day tournament. © 2011 Taylor & Francis

Physiological responses and time-motion characteristics of various small-sided soccer games in youth players

The aim of this study was to examine acute physiological responses and time-motion characteristics associated with three different small-sided soccer game formats in youth players. Sixteen male soccer players aged 16.3 ± 0.6 years (mean ± s) completed three variations of a small-sided game (i.e. 2 vs. 2, 4 vs. 4, and 6 vs. 6 players) in which heart rate, rating of perceived exertion (RPE), blood lactate concentration, and time-motion characteristics were recorded. The pitch size was altered to keep the relative pitch area per player consistent for each game format. The 2 vs. 2 games exhibited greater blood lactate, heart rate, and RPE responses compared with 4 vs. 4 and 6 vs. 6 games (P < 0.05). The players travelled less (P < 0.05) distance at speeds of 0-7 km · h-1 in the 4 vs. 4 compared with the 2 vs. 2 games (1128 ± 10 m and 1176 ± 8 m, respectively). Average maximal sprint distances above 18 km · h-1 were lower (P < 0.05) in 2 vs. 2 than in 4 vs. 4 and 6 vs. 6 games (11.5 ± 3.9 m, 15.3 ± 5.5 m, and 19.4 ± 5.9 m, respectively), and in 4 vs. 4 compared with 6 vs. 6 games. The results show that as small-sided game formats decrease in size and relative pitch area remains constant, overall physiological and perceptual workload increases

Monitoring for overreaching in rugby league players

The aim of this study was to identify indicators of non-functional overreaching (NFOR) in team sport athletes undertaking intensive training loads. Eighteen semi-professional rugby league players were randomly assigned into two pair matched groups. One group completed 6 weeks of normal training (NT) whilst the other group was deliberately overreached through intensified training (IT). Both groups then completed the same 7-day stepwise training load reduction taper. Multistage fitness test (MSFT) performance, , peak aerobic running velocity (V max), maximal heart rate, vertical jump, 10-s cycle sprint performance and body mass were measured pre- and post-training period and following the taper. Hormonal, haematological and immunological parameters were also measured pre-training and following weeks 2, 4 and 6 of training and post-taper. MANOVA for repeated measures with contrast analysis indicated that MSFT performance and were significantly reduced in the IT group over time and condition, indicating that a state of overreaching was attained. However, the only biochemical measure that was significantly different between the IT and NT group was the glutamine to glutamate (Gln/Glu) ratio even though testosterone, testosterone to cortisol (T/C) ratio, plasma glutamate, and CK activity were significantly changed after training in both groups. Positive endurance and power performance changes were observed post-taper in the IT group confirming NFOR. These changes were associated with increases in the T/C ratio and the Gln/Glu ratio and decreases in plasma glutamate and CK activity. These results indicate that although there was no single reliable biochemical marker of NFOR in these athletes, the Gln/Glu ratio and MSFT test may be useful measures for monitoring responses to IT in team sport athletes

Coastal Scenery Assessment by Means of a Fuzzy Logic Approach

Landscape is a major element affecting people's life quality and coastal landscape evaluation is strongly rooted in the man-environment tradition. Coastal areas, all over the world, are under threat due to the conflicting requirements that rely on natural scenery of such as habitation, recreation, and industry. Since 'coastal scenery' is a natural resource, it has to be evaluated in an objective and quantitative way to provide a means of comparison against coastal activities and for environmental impact assessments. This chapter presents an evidence-based methodology called 'Coastal Scenic Evaluation System ( CSES)'. It is a technique that can be used not only for landscape preservation and protection, but also as scientific tool for envisaged coastal management and future development based upon plans formulated by an evidence-based approach. The results provide base-line information for a sound coastal management decision especially regarding intensive urban and industrial developments. CSES uses fuzzy logic to reduce subjectivity on decisions and obtain a quantitative evaluation of public survey research on 26 coastal scenic parameters having both physical and human perceptual characteristics. The weights of the scenic parameters were estimated by public survey questionnaires for Turkey, UK, Malta and Croatia and via consultations with coastal experts from the above mentioned four countries and Australia, Ireland, USA and Japan. Fuzzy logic mathematics was used to calculate a coastal scenic evaluation index ( D) from the checklist of 26 scenic parameters by using the attributed weights of the parameters which enabled to categorize scenic values of the coastal areas into five distinct classes

Effects of a very congested match schedule on body-load impacts, accelerations, and running measures in youth soccer players

PURPOSE: To analyze the effects of a very congested match schedule on the total distance (TD) covered, high-intensity-running (HIR) distance, and frequency of accelerations and body-load impacts (BLIs) performed in a team of under-15 soccer players (N=10; 15.1±0.2 y, 171.8±4.7 cm, 61±6.0 kg) during an international youth competition. METHODS: Using global positioning systems, player performances were repeatedly monitored in 5 matches performed over 3 successive days. RESULTS: Significant differences were observed between matches (P<.05) for the frequency of accelerations per minute, BLIs, and BLIs per minute. No differences were observed for the TD covered, TD run per minute, number of high-intensity runs, distance covered in HIR, per-minute peak running speed attained, or frequency of accelerations. The frequency of accelerations per minute decreased across the competition while BLIs were higher during the final than in all other matches. CONCLUSIONS: These results suggest that BLIs and acceleration might be used as an alternative means to represent the external load during congested match schedules rather than measures related to running speed or distance covered