Seasonal Changes in Strength and Power in Elite Rugby League: A Systematic Review and Meta-Analysis

Abstract

The ability of a rugby league player to express high levels of strength and power is crucial for success in competition. Although researchers have shown relationships between physical attributes and performance, there is a lack of information related to changes in strength and power across various phases of the season. The purpose of this review was to identify the magnitude of change in muscular strength and power during different phases of an elite rugby league season. Percentage change and effect size were calculated to evaluate the magnitude of changes in strength and power. Meta-analyses were conducted to provide pooled estimates and 95% confidence intervals. Twelve studies were included; six reported changes following pre-season training, two during the competition phase and four examined changes over multiple seasons. Pooled estimates indicated large increases in upper and lower body strength 0.81 [0.43-1.19] and 1.35 [0.79-1.91], respectively, following pre-season training. Studies incorporating predominantly heavier loads (p 80% 1 RM) in training reported greater increases in maximal strength than studies completing lighter loads. Four studies used a wave-like programming strategy to obtain large improvements in strength and power 0.91 [0.36-1.45] and 0.90 [0.22-1.57], over multiple seasons. The results of this review highlight the limited current evidence and provides a preliminary reference point for strength and conditioning coaches aiming to develop and maintain strength and power across various stages, and over multiple seasons. Importantly, the results also indicate that higher loads result in greater increases in strength than lower loads.

Longitudinal changes in anthropometric, physiological, and physical qualities of international women’s rugby league players

“…Comparing these results with previous research, the mean isometric mid-thigh pull peak force for Australian women’s backs (+369 N) and forwards (+515 N) surpassed the values found for backs and forwards in this study [9]. Maximal strength is a pivotal determinant of successful rugby league performance, correlating with improved technical skill, greater match-play distances covered, enhanced sprint performance, and higher playing standards [37,39]. Hence, prioritising maximal strength development during the pre-season period is crucial, as this phase often yields more noticeable strength improvements compared to the in-season phase [37].…”

Changes in strength and jump performance over a 10 week competitive period in male collegiate golfers

“…Taking into account the changes in both tests, it appears that male collegiate golfers show similar seasonal effects to other sports where explosive lower body movements such as the vertical jump task have been maintained or improved while changes in strength appear to be less consistent. [18][19][20] Specifically, concerning strength changes, the current study displays this inconsistency. Peak force was reduced to a nonsignificant level while force at 100, 200, and 300 ms each showed significant reductions.…”

“…Findings from this investigation are similar to those seen across other sports with reductions in strength and maintenance of vertical jump abilities. [18][19][20][21] Additionally, this investigation sought to use a single-subject analysis to identify if group means were caused by a large shift from single participants as golf is an individual sport. We found that general trends existed for each variable of interest however, each variable also displayed individuals having opposing changes over the course of the ten weeks.…”

“…This supports previous investigations that saw lower body power increase over a competitive season. 19,20 Previous investigations have shown that jump height has limited associations with golf performance, in particular clubhead velocity. 3,5 However, other force-related CMJ variables did show significant relationships to clubhead velocity.…”

Seasonal Variation and Positional Differences in Anthropometry, Strength, and Power Characteristics in English Premiership Women's Rugby Union Players

“…The seasonal nature presents a variety of physical challenges that can cause fluctuations in a player's physical development during the season (22); these include a decrease in resistance training load to allow for increases in the volume of technical and tactical skill training. In addition, muscle damage and inflammation after a match, potentially causing decrements in muscle performance, may be problematic for developing or maintaining muscular strength and power (17,35). Hence, the players' ability to acquire and maintain appropriate body composition and physical characteristics, both preseason and in-season, is of paramount importance.…”