A Biomechanical Review of the Techniques Used to Estimate or Measure Resistive Forces in Swimming

Abstract

Resistive or drag forces encountered during free swimming greatly influence the swim performance of elite competitive swimmers. The benefits in understanding the factors which affect the drag encountered will enhance performance within the sport. However, the current techniques used to experimentally measure or estimate drag values are questioned for their consistency, therefore limiting investigations in these factors. This paper aims to further understand how the resistive forces in swimming are measured and calculated. All techniques outlined demonstrate both strengths and weaknesses in the overall assessment of free swimming. By reviewing all techniques in this area, the reader should be able to select which one is best depending on what researchers want to gain from the testing.

Developing a methodology for estimating the drag in front-crawl swimming at various velocities

“…For Da, previous studies reported quite different results because of the differences in the anthropometric and technical characteristics of the swimmers observed as well as because of the differences in the adopted methodologies. All these adopted methodologies have their pros and cons (for a discussion on this point, the reader is referred to papers by Sacilotto, Ball, and Mason (2014), Toussaint et al (2004), and Zamparo et al (2009)). For these same reasons, despite the difficulty in directly comparing our data with that reported in the literature, our results indicate that Da values obtained using MRT are larger than Dp; this agrees with the findings of some previous studies (e.g., Di Prampero et al, 1974;Formosa et al, 2012;Gatta, Cortesi, Fantozzi, & Zamparo, 2015;Zamparo et al, 2009) but not with others in which Da was reported to be equal (or even lower) than Dp (e.g., Hollander et al, 1986;Toussaint et al, 1988;Toussaint et al, 2004;Van der Vaart et al, 1987).…”

Hydrodynamic profile of young swimmers: Changes over a competitive season

“…The following can be addressed as main limitations: (a) there is no technique to assess drag force that might be considered as gold standard. Some care should be exercised when comparing data collected with different procedures (e.g., for active drag – VPM vs ATM vs MAD system vs CFD; for passive drag – glide decay vs strain gauge vs ATM vs CFD) (e.g., Sacilotto et al., ). (b) This is the first time that non‐linear parameters, such as ApEn , are reported in competitive swimming.…”

Rip Current Generation, Flow Characteristics and Implications for Beach Safety in South Florida

“…The effect of rip currents on the drag force and power have to be derived through numerical simulation of the interaction between rip currents and the human body by combining the models for rip currents (Castelle et al, 2016a) and swimming movements (Li and Zhan, 2015;Rouboa et al, 2006), and through expanding indoor experiments (Alcock and Mason, 2007;Hazrati, 2016;Sacilotto et al, 2014) to measure various body resistant forces, energy consumption rates, and fatigue rates in a flowing-water setting.…”

“…Limited evidence from comparing modeled hazard likelihood with observed rip current speeds suggests that rip currents with speeds greater than 0.2 m/s may be hazardous (Moulton et al, 2017). More accurate boundaries should be determined through experiments similar to measure the active drag force (Sacilotto et al, 2014). A quadratic relationship has been employed to calculate the active drag force in terms of speed in this paper.…”

“…Many studies on the drag force caused by swimmers have been done in the field of biomechanics (Hazrati, 2016;Sacilotto et al, 2014;Toussaint et al, 2002). The drag force produced by swimmers is composed of skin friction drag, form (or pressure) drag associated with the pressure difference between the head and toe of a swimmer, and wave drag caused by the movement of the swimmer through the surface of water (Vorontsov and Rumyantsev, 2000b;Webb et al, 2011).…”