Two minutes after completing the passive ROM trials the
subjects performed either the CR or SRC stretching intervention.
During the CR condition the ankle was passively
rotated at 0.087 rad s
−1
until reaching the point of discomfort,
a position regularly used in stretch studies (Blazevich
et al. 2012; Kay and Blazevich 2008, 2009a). The movement
velocity was too slow to elicit a significant myotatic
stretch reflex response, which ensured that full ROM
was achieved and substantial stress was applied to the
MTC (McNair et al. 2001). Furthermore, this ensured that
moment data were reflective of the passive properties of the
MTC. The subjects’ ankles were held in the stretched position
for 10 s and followed immediately with a 5-s ramped
maximal isometric contraction (peak joint moment was
obtained after ~3 s from contraction initiation and held
for ~2 s) performed with the muscle at full stretch (i.e.,
point of discomfort). Upon contraction cessation, the ankle
was then immediately rotated again at 0.087 rad s
−1
until
reaching the point of discomfort with the protocol repeated
three further times giving a total duration of 60 s (i.e., 4 ×
10-s stretches and 4 × 5-s contractions). The constant angle
stretching method was chosen during the static stretching
phase of the CR stretching technique as increasing ROM
during the stretches (constant torque) may introduce differing
levels of strain between conditions (Herda et al. 2014),
which would have compromised our ability to determine
whether muscle length during the contraction phase influenced
ROM. Furthermore, the static stretch phase duration
(10 s) was considered too short to enable further meaningful
or reliable increases in ROM prior to the contraction
phase. During the SRC protocol the static stretch phase was
performed identically, however after the 10 s of stretching
the ankle was returned to the anatomical position where the
5-s ramped maximal isometric contraction was performed.
The ankle was rotated again 0.087 rad s
−1
until reaching
the point of discomfort with the protocol repeated three
times giving a total duration of 60 s. Two minutes later the
subjects repeated the passive and active trials (see Fig. 1).