Introduction. The impact of different types of warm-up protocol on children’s performance is clearly an unresolved issue that has not yet been satisfactorily investigated. Consequently, the purpose of this review was to analyze the current literature on the subject. Material and Methods. The first step was to perform a search in PROSPERO with the keyword warm up. After that, five electronic bibliographic databases were searched through until April 10th, 2021: Web of Science (all databases), Scopus, SportDiscus, PubMed, and Google Scholar. Results. Six studies involving a total of 138 participants were included in the final analyses. Regarding the physical qualities that were assessed, 4 of the studies assessed strength through the vertical jump, 3 assessed running speed, one assessed anaerobic endurance (30 seconds) with a cycle ergometer and another assessed flexibility using the Sit & Reach. Conclusions. The practice of dynamic or specific warm-up before training appears to improve speed and strength performance compared to no warm-up in school-age children. However, the effects of warm-up on endurance and flexibility performance in school-age children need to be further investigated.

Before starting any physical activity, it is common to warm-up. However, the effects of including stretching in the warm-up remain controversial, and so does the most appropriate type of stretching depending on the activity to be performed afterwards. Thus, the aim of this article is to establish a systematic review protocol to analyze the effects of including different types of stretching in the warm-up on motor performance. The different basic physical abilities (strength, endurance, speed, flexibility) and coordinative abilities (coordination, balance, agility) will be analyzed. To this end, a systematic review will be carried out by examining eight electronic databases (Web of Science™ (all databases), Scopus, SPORTDiscus with Full Text, Pub-Med, CINAHL, Cochrane Library Plus, ProQuest Dissertations & Theses Global™ and WorldCat), along with carrying out a complementary search phase (snowballing). This will be followed by a meta-analysis, where each selected study will be coded (study characteristics, participant characteristics, intervention characteristics, intervention outcomes) using an ad hoc code established by the research group and previously tested on a sample of studies at the beginning of the review. To ensure the methodological quality of the systematic review, as well as its accuracy and transparency, the PRISMA-P and Cochrane Handbook protocol for systematic reviews will be employed.