Fig. 4

a Average (plain line) and standard deviation (shaded areas) of the force output in Newtons (N) during the 30-s unilateral exercise for the female group (average: red plain line; standard deviation: red shaded area) and for the male group (average: blue plain line; standard deviation: blue shaded area). b Representative recordings of the force output in Newtons (N) during the 30-s unilateral exercise for one male (black trace) and one female (red trace). c, d Representative recordings of the female participant’s surface electromyographic root mean square (sEMG RMS) of the exercising limb (EL—panel c) and the non-exercising limb (NEL—panel d), vastus lateralis (blue trace), vastus medialis (black trace), and rectus femoris (red trace) during the 30-s unilateral exercise. e, f Representative recordings of the male participant’s surface electromyographic root mean square (sEMG RMS) of the exercising limb (EL—panel e) and the non-exercising limb (NEL—panel f), vastus lateralis (blue trace), vastus medialis (black trace), and rectus femoris (red trace) during the 30-s unilateral exercise