Effects of Sprint Interval Training Surface on Physical Fitness Attributes of Collegiate Female Soccer Players: Identifying Individual Responses to Training on Grass, Sand, and Land Surfaces.

This study aimed to identify the optimal surface for sprint interval training to maximize transfer effects on physical performance measures on the grass pitch. Using a randomized controlled trial design, 40 collegiate female soccer players were equally assigned to three experimental groups performing short sprint interval training (SSIT: 4 sets of 10 repetitions with 5 seconds all-out running, with a 50-second recovery period between each effort and a 3-minute rest interval between sets) on SAND, GRASS, LAND, and a control group. Before and after a 7-week training period, participants underwent a series of field-based tests to evaluate countermovement jump (CMJ), 20-m linear sprint, Illinois change of direction (CoD) speed, Yo-Yo IR1, 2.4 km time trial, and maximal kicking distance (MKD) performance. A two-way analysis of variance with repeated measures was conducted on the data, along with Bonferroni post hoc testing. After the intervention, the control group did not show any changes, while the SAND, GRASS and LAND training groups demonstrated improvements (p = 0.001) in their performance as follows: CMJ (effect size [ES] = 1.21, 0.97, 0.64), 20-m linear sprint (ES = -0.81, -0.55, -0.41), Illinois CoD (ES = -0.72, -0.79, -0.41), Yo-Yo IR1 (ES = 1.86, 1.19, 1.12), 2.4 km time trail (ES = -0.82, -0.62, -0.49), and MKD (ES = 0.60, 0.90, 0.72), respectively. Comparative analysis of SAND, GRASS, and LAND revealed that performing SSIT on SAND results in a significantly greater gain in CMJ than LAND (p = 0.041). Analyzing individual responses to training interventions indicated that the training surface had a favorable influence on CMJ (SAND vs. LAND, p = 0.009), but on other variables no statistically significant (p > 0.05) differences were observed. Considering these findings, it is advised that strength and conditioning coaches use the SAND surface as the initial choice for SSIT sessions regarding greater gains (i.e., ES) in performance. This recommendation aims to facilitate more favorable transfer in physical fitness adaptation on a soccer grass pitch. In case of unavailability of SAND surface, GRASS surface would be a suitable alternative to enhance the physical fitness of collegiate female soccer players.

Enhancing Gpx1 palmitoylation to inhibit angiogenesis by targeting PPT1.

The significance of protein S-palmitoylation in angiogenesis has been largely overlooked, leaving various aspects unexplored. Recent identification of Gpx1 as a palmitoylated protein has generated interest in exploring its potential involvement in novel pathological mechanisms related to angiogenesis. In this study, we demonstrate that Gpx1 undergoes palmitoylation at cysteine-76 and -113, with PPT1 playing a crucial role in modulating the depalmitoylation of Gpx1. Furthermore, we find that PPT1-regulated depalmitoylation negatively impacts Gpx1 protein stability. Interestingly, inhibiting Gpx1 palmitoylation, either through expression of a non-palmitoylated Gpx1 mutant or by expressing PPT1, significantly enhances neovascular angiogenesis. Conversely, in PPT1-deficient mice, angiogenesis is notably attenuated compared to wild-type mice in an Oxygen-Induced Retinopathy (OIR) model, which mimics pathological angiogenesis. Physiologically, under hypoxic conditions, Gpx1 palmitoylation levels are drastically reduced, suggesting that increasing Gpx1 palmitoylation may have beneficial effects. Indeed, enhancing Gpx1 palmitoylation by inhibiting PPT1 with DC661 effectively suppresses retinal angiogenesis in the OIR disease model. Overall, our findings highlight the pivotal role of protein palmitoylation in angiogenesis and propose a novel mechanism whereby the PPT1-Gpx1 axis modulates angiogenesis, thereby providing a potential therapeutic strategy for targeting PPT1 to combat angiogenesis.