Here's another approach, using spread() from the tidyr package.
library(tidyr)
df <- data.frame(stringsAsFactors = FALSE,
V1 = c("Gender", "Weight", "Height", "Age"),
V2 = c("Male", "75 kg", "175 cm", "21")
)
df
#> V1 V2
#> 1 Gender Male
#> 2 Weight 75 kg
#> 3 Height 175 cm
#> 4 Age 21
spread(df, V1, V2)
#> Age Gender Height Weight
#> 1 21 Male 175 cm 75 kg
Created on 2019-02-07 by the reprex package (v0.2.1)