Fluid-electrolyte balance associated with tennis match play in a hot environment.
Twenty (12 male and 8 female) tennis players from two Division I university tennis teams performed three days of round-robin tournament play (i.e., two singles tennis matches followed by one doubles match per day) in a hot environment (32.2 +/- 1.5 degrees C and 53.9 +/- 2.4% rh at 1200 hr), so that fluid-electrolyte balance could be evaluated. During singles play, body weight percentage changes were minimal and were similar for males and females (males -1.3 +/- 0.8%, females -0.7 +/- 0.8%). Estimated daily losses (mmol.day-1) of sweat sodium (Na+) and potassium (K+) (males, Na+ 158.7, K+ 31.3; females, Na+ 86.5, K+ 18.9) were met by the players' daily dietary intakes (mmol.day-1) of these electrolytes (males, Na+ 279.1 +/- 109.4, K+ 173.5 +/- 57.7; females, Na+ 178.9 +/- 68.9, K+ 116.1 +/- 37.5). Daily plasma volume and electrolyte (Na+, K+) levels were generally conserved, although, plasma [Na+] was lower (p < .05) on the morning of Day 4. This study indicated that these athletes generally maintained overall fluid-electrolyte balance, in response to playing multiple tennis matches on 3 successive days in a hot environment, without the occurrence of heat illness.
Bergeron
M F
MF
Department of Health Science, College of Health, University of N. Florida, Jacksonville 32224, USA.
Maresh
C M
CM
Armstrong
L E
LE
Signorile
J F
JF
Castellani
J W
JW
Kenefick
R W
RW
LaGasse
K E
KE
Riebe
D A
DA
D000293:Adolescent; D000328:Adult; D000450:Aldosterone / Q000097:blood; D000704:Analysis of Variance; D002149:Energy Intake; D004734:Energy Metabolism / Q000502:physiology; D005260:Female; D006400:Hematocrit; D006358:Hot Temperature; D006801:Humans; D008297:Male; D009994:Osmolar Concentration; D011188:Potassium / Q000097:blood / Q000652:urine; D012964:Sodium / Q000097:blood / Q000652:urine; D013546:Sweating / Q000502:physiology; D013715:Tennis; D014882:Water-Electrolyte Balance / Q000502:physiology*
D000450:Aldosterone; D012964:Sodium; D011188:Potassium