BACKGROUND Ice swimming for 1 mile and 1 km is a new discipline in open-water swimming since 2009. This study examined female and male performances in swimming 1 mile ('Ice Mile') and 1 km ('1 km Ice event') in water of 5 °C or colder between 2009 and 2015 with the hypothesis that women would be faster than men. METHODS Between 2009 and 2015, 113 men and 38 women completed one 'Ice Mile' and ...

As their swimming speed increased, bluegill sunfish (Lepomis macrochirus) switched from pectoral-fin-powered labriform swimming to undulations of the body axis. This gait transition occurred at a mean swimming speed of 0.24+/-0.01 m s(-1) and a pectoral fin beat frequency of 2.79+/-0.11 Hz (mean +/- s.e.m., N=6). The power output available from the main upstroke (adductor profundus) and downstr...

Sexual selection can increase morphological diversity within and among species. Little is known regarding how interspecific variation produced through sexual selection affects other functional systems. Here, we examine how morphological diversity resulting from sexual selection impacts aerobic locomotor performance. Using Xiphophorus (swordtail fish) and their close relatives (N = 19 species), ...

This study examines the use of optical trapping as a quantitative measure of sperm motility. The effects of laser trap duration and laser trapping power on sperm motility are described between sperm swimming force, swimmimg speed, and speed of progression (SOP) score. Sperm (SOP scores of 2-4) were trapped by a continuous-wave 1064 nm single-point gradient laser trap. Trap duration effects were...

The kinematics of plaice (Pleuronectes platessa, L=22.1 cm) and cod (Gadus morhua, L=25.0 cm, where L is total fish length) swimming at various speeds at the bottom and lifted to heights, h, of 10, 50 and 100 mm by a thin-wire grid were measured. For cod, tailbeat frequency, amplitude, body and fin span and propulsive wavelength were unaffected by h and varied with speed as described for fusifo...

6. Thrust power (= drag power) calculated using Lighthill's small amplitude bulk momentum model was two to three times the theoretical minimum of a flat plate of equivalent length and area moving parallel to the flow with a presumed turbulent boundary layer. 7. Froude efficiency increased with swimming speed, and it is shown that this is the usual relationship for fish studied so far. Froude ef...

BACKGROUND This study investigated swimming speeds and sex differences of finalists competing at the Olympic Games (i.e. 624 female and 672 male athletes) and FINA World Championships (i.e. 990 women and 1008 men) between 1992 and 2013. METHODS Linear, non-linear and multi-level regression models were used to investigate changes in swimming speeds and sex differences for champions and finalis...

Simultaneous swimming kinematics and hydrodynamics are presented for American eels, Anguilla rostrata, swimming at speeds from 0.5 to 2 L s(-1). Body outlines and particle image velocimetry (PIV) data were collected using two synchronized high-speed cameras, and an empirical relationship between swimming motions and fluid flow is described. Lateral impulse in the wake is estimated assuming that...

Whirligig beetles (Coleoptera: Gyrinidae) are semi-aquatic insects with a morphology and propulsion system highly adapted to their life at the air-water interface. When swimming on the water surface, beetles are subject to both fluid resistance and wave resistance. The purpose of this study was to analyse swimming speed, leg kinematics and the capillarity waves produced by whirligig beetles on ...

cAMP and cGMP had distinct effects on the regulation of ciliary motility in Paramecium. Using detergent-permeabilized cells reactivated to swim with MgATP, we observed effects of cyclic nucleotides and interactions with Ca2+ on the swimming speed and direction of reactivated cells. Both cAMP and cGMP increased forward swimming speed two- to threefold with similar half-maximal concentrations nea...