**2. Methods**

The current study intended to summarize the findings and evidence reported in the literature about the effect of warm-up protocols in force production, strength evaluation and resistance training. In order to identify relevant articles on this topic, an extensive bibliographic search was carried out. Of all the articles identified, only nine were chosen, which corresponded to the theme addressed here.

#### **2.1 Search strategy**

A search in the literature that studied different types of warm-up was conducted, where the focus was to understand the effects of warm-up in strength performance. Considering that active warm-up is the most commonly used by people engaged in sports and physical exercise and that is the most investigated, it was only included original articles that focused on the effects of active warm-up. Original research articles published between 2010 and 2020 were selected to identify studies in which warm-up and strength performance were reported. The search for scientific articles was performed in 4 databases (Web of Science, Scopus, PubMed and ScienceDirect) in which the keywords "warming-up", "resistance training" and "strength" with multiple combinations were used and with no restrictions of language.

#### **2.2 Inclusion and exclusion procedures**

To carry out this research, the studies had to respect inclusion criteria such as, being focused on active warm-up, being cross-sectional studies, focusing on measures of strength, being carried out by healthy individuals, aged 18 years or over. As exclusion criteria, all types of review (qualitative review, systematic review and meta-analysis) were excluded, the non-use of at least one active warm-up and studies with young participants (<18 years old). Articles that were not written in English were also excluded.
