External Validity of the T-SAFT90: A Soccer Simulation Including Technical and Jumping Activities

Abstract

Purpose: To examine the physiological, muscle-damage, endocrine, and immune responses to a modified soccer-simulation protocol to include technical and jumping activities characteristic of match play (the Technical Soccer-Specific Aerobic Field Test; T-SAFT90). Methods: Eighteen university players (age 23 [2] y, stature 175 [5] cm, body mass 74 [11] kg) performed the 90-minute protocol, with acute physiological responses monitored via heart rate, ratings of perceived exertion (6–20 scale), and body mass changes. Creatine kinase, myoglobin, cortisol, and leukocyte subset concentrations were measured at baseline, immediately (0 h), and 24 hours post T-SAFT90. Results: T-SAFT90 incurred an average heart rate equivalent to 87% (5%) of maximum, 16 (2) a.u. ratings of perceived exertion, and a 1.5% (1.0%) body mass deficit. Moderate to large proliferation of leukocyte subsets (P ≤ .01; leukocytes: 6.4-fold; neutrophils: 5.5-fold; lymphocytes: 2.0-fold) and increases in cortisol (2.3-fold) were observed at 0 hours (effect size = 1.13–3.52), each returning to baseline by 24 hours (P > .45; effect size = 0.05–0.50). Myoglobin peaked immediately post T-SAFT90 (4.8-fold), whereas creatine kinase (24 h: 6.0-fold) showed a delayed time course (both P ≤ .001; very large effects; effect size = 2.66 and 3.43, respectively). Conclusions: The magnitude and time course of the physiological, immune, endocrine, and muscle-damage markers observed during and following T-SAFT90 are similar to values reported in match-play literature, demonstrating external validity of the simulation.

Low-fat, lactose-free and leucine-enriched chocolate cow milk prototype: A preliminary study on sensorial acceptability and gastrointestinal complaints following exhaustive exercise

“…Furthermore, this ready-to-drink sport-specific drink was evaluated on sensorial acceptability and gastrointestinal complaint scores using football players as potential consumers in an ecological team sport workload and recovery in a real sporting setting. The FMP (adapted SAFT 90 ) had similar physiological [ 39 ] or mechanical load [ 29 ] to football games, reinforcing the validity of the protocol as an instrument for fatigue induction corresponding to an official football match as demonstrated in the external validation study of this protocol [ 30 ].…”

“…Thus, the bloating gastrointestinal complaint impact of CML was small, considering that other conditions and workload characteristics in team players could aggravate the sensation of gastrointestinal discomfort. In this scope, the present study used a trial which simulates a football match-related fatigue via standardized protocol [ 29 , 30 ]. Thus, gastrointestinal or appetite problems could be expected following this exhaustive exercise, as already presented in literature.…”

“…In the first visit, the athletes were characterized (weight and height) and familiarized using a standardized 90min football-match simulation protocol (FMP) [29,30]. The energetic value of the athletes' habitual intake was determined by registering their usual food diet during three consecutive days, and also including their average weekend consumption [31].…”

“…The hydration in FMP occurred with water (2 mL.kg [BW] − 1 ) every 15 min up to 75 min to ensure adequate hydration [32]. FMP was a 90-min fatiguing exercise protocol (T-SAFT 90 ) corresponding to an official football match played from audio commands [29,30]. Each player used a strap equipment component of Polar Team System® (Polar Electro Oy, Kempele, Finland).…”

The effect of physical fatigue on the performance of soccer players: A systematic review

“…Therefore, the most recent research in the area has been using physical protocols more applied to soccer, in order to simulate the physical demands of the game and the duration of the game [ 32 , 36 , 41 ]. Although they present an advance in relation to the applicability and representativeness of the soccer game, these protocols, for the most part, do not include actions of acceleration, deceleration, changes of direction, jumps and ball actions, which are present demands during the game and which generate an increase in the physical wear of the players [ 43 ]. Thus, it is important to pay attention to the particular characteristics of physical tests, since there is evidence that demonstrates that different physical protocols can modify the performance of players [ 26 , 44 ].…”