{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T15:25:50Z","timestamp":1787239550665,"version":"build-2736575974"},"reference-count":48,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2025,10,14]],"date-time":"2025-10-14T00:00:00Z","timestamp":1760400000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Objective: The purpose of this study is to investigate the effects of back squat (BS) and squat jump (SJ) on the maximum-striking strength and speed-striking strength of the jab and cross of elite male boxers, and to identify the time point of the post-activation performance enhancement (PAPE) induced by these two activation methods. Methods: A total of 29 Chinese male boxers were recruited to participate in four different intensities of muscle activation through BS and SJ exercises (BS50%, SJ50%, BS80%, SJ80%). The participants were tested on their jab and cross using specialized testing protocols at recovery intervals of 4, 8, 12, and 16 min (speed-striking strength testing was conducted first, followed by maximum-striking strength testing), and the maximum-striking strength and speed-striking strength of the athletes were recorded. Results: (1) Maximum-striking strength: For the jab, the results indicated that there were significant differences between BS50% at 8 min and 12 min and the baseline (p &lt; 0.01), and between SJ50% at 4, 8, and 12 min and the baseline (p &lt; 0.01). BS80% showed significant differences at 12 min compared to baseline (p &lt; 0.01), and the SJ80% exhibited significant differences at 8 min (p &lt; 0.05) and 12 min (p &lt; 0.01) compared to baseline. For the cross, BS50% demonstrated significant differences at 12 min compared to baseline (p &lt; 0.01), and SJ50% showed significant differences at 8 min and 12 min (p &lt; 0.01). Both BS80% and SJ80% revealed significant differences at 8, 12, and 16 min compared to baseline (p &lt; 0.01). (2) Speed-striking strength: For the jab, there were no significant differences between BS50% and SJ50% at all time intervals compared to baseline (p &gt; 0.05). BS80% showed a significant difference at 4 min compared to baseline (p &lt; 0.05), and SJ80% exhibited significant differences at 12 min compared to baseline (p &lt; 0.01). For the cross, there were no significant differences between BS50%, SJ50%, and BS80% at all time intervals compared to baseline (p &gt; 0.05), while SJ80% demonstrated significant differences at 8 min and 12 min compared to between (p &lt; 0.01). The results showed that PAPE significantly enhanced maximum punch force at 8\u201312 min across several activation conditions. In contrast, improvements in speed-striking force were only observed following high-load squat jump (SJ at 80% 1 RM), with significant increases at 8 min for the cross and at 12 min for the jab, whereas BS or lower-load SJ produced no meaningful changes. Conclusions: PAPE activation significantly enhances the striking force of boxers at the recovery interval of 12 min, but the effect is influenced by the intensity and method of activation. High-load activation can enhance the striking strength of boxers more rapidly and sustainably, and high-load SJ are more beneficial for the speed-striking strength of boxers.<\/jats:p>","DOI":"10.3390\/s25206356","type":"journal-article","created":{"date-parts":[[2025,10,15]],"date-time":"2025-10-15T08:34:26Z","timestamp":1760517266000},"page":"6356","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Post-Activation Potentiation\u2019s Impact on Specialized Strike Strength in Elite Male Boxers: An Acute Study"],"prefix":"10.3390","volume":"25","author":[{"given":"Yongfu","family":"Liu","sequence":"first","affiliation":[{"name":"School of Physical Education, University of Jinan, Jinan 250022, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rangxi","family":"Jin","sequence":"additional","affiliation":[{"name":"School of Athletic Performance, Shanghai University of Sport, Shanghai 200438, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chao","family":"Chen","sequence":"additional","affiliation":[{"name":"College of Physical Education, Dalian University, Dalian 116622, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"337","DOI":"10.1007\/s40279-014-0274-7","article-title":"Amateur Boxing: Physical and Physiological Attributes","volume":"45","author":"Tabben","year":"2015","journal-title":"Sports Med."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"146","DOI":"10.1002\/tsm2.71","article-title":"A Damaging Punch: Assessment and Application of a Method to Quantify Punch Performance","volume":"2","author":"Dunn","year":"2019","journal-title":"Transl. 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