Biomechanics and Medicine in Swimming XI

Bench Press and Leg Press Strength and its
Relationship with In-Water Force and Swimming
Performance when Measured in-season in Male and
Female Age-group Swimmers
carl, d.l., leslie, n., dickerson, t., Griffin, B., Marksteiner, A.
University of Cincinnati, Cincinnati Ohio, USA
The purpose of this study was to determine if two standard measurements
of dry land strength would correlate with the ability to generate
in-water force. Participants were 25 male and female age-group swimmers.
One repetition max lifts were established for the Bench Press (BP)
and Leg Press (LP) and correlated with in-water force generation as
measured during tethered swimming (TeS). They were also correlated
with swimming performance using a timed 22.9-m (25y) swim. A significant
correlation existed between BP strength and both TeS and 25y
tests (r = 0.82 and 0.84 respectively, p< 0.01) A minor correlation existed
between LP and 25y (R = 0.70, p< 0.01). No significant correlation existed
between LP and TeS (r= 0.50, p< 0.01). In addition, males demonstrated
stronger correlations than females in all cases. In conclusion,
BP strength may be an appropriate alternative to established methods as
an indicator of in-water force generation and swimming performance in
older age-group swimmers.
Key words: swimming, tethered swimming, Bench Press, leg Press
IntroductIon
In recent years, USA-Swimming launched a series of educational programs
and databases designed to quickly and efficiently disseminate
information to their entire coaching membership. One such program
is the Land / Water Strength Test (LWST; Sokolovas, 2007 and USA-
Swimming, 2007) database. The purpose of the LWST is to assess
swimming-specific strength on land and to determine how effectively
it transfers into the generation of force while in the water. Depending
upon the relationship observed, a coach could make personalized adjustments
in the swimmers strength training program and or their stroke efficiency.
If the relationship is high between land and water strength then
it might be suggested that the coach design a resistance training program
to enhance overall strength in an effort to improve performance.
Conversely, if the relationship is low it would be desirable for the coach
and athlete to focus on correcting stroke efficiency, more so, than the
overall strength of the swimmer.
To assess dry land strength, USA-Swimming recorded maximum
effort strength during isometric contractions on a Vasa Trainer swim
bench. To our knowledge, additional testing measures have not been
conducted to determine whether other forms of land strength are equally
beneficial in establishing discrepancies between land and in-water
strength measurements. Therefore, it was the purpose of this study to
determine if two standard measurements of dry land strength, bench
press (BP) and leg press (LP), would correlate with the ability to generate
force in water, as measured during tethered swimming, and whether
they would correlate with sprint swimming performance as measured by
a timed 22.9m swim.
Methods
Twenty five (10 male, 15 females) highly competitive age-group swimmers
ranging from National qualifiers to High School competitors volunteered
to participate in the study. Their mean (+ SD) age, weight and
height were 16.6 + 1.3 years, 71.6 + 17.3 kg, and 181.6 + 3.8 cm for males
and 16.3 + 0.9 years, 62.0 + 2.9 kg, and 168.2 + 4.6 cm for females respectively.
Each participant in the study trained on a year-round basis. The
study was approved by the institutional review board at the University of
Cincinnati with all subjects completing an informed consent document.
chaPter4.trainingandPerformance
Each subject completed a single day testing session that consisted
of a randomized distribution of the following activities:
Swim Training: Prior to the in-water testing, each subject completed
a standardized 1371-m warm-up. Completion of the 2 in-water tests
was completed in randomized order. 22.9-m Swim Test: Each subject
completed two 22.9-m maximal effort swims from the starting block.
Each swim was separated by a minimum of 5 minutes. Active recovery
swimming was allowed at the discretion of each subject. Times were
recorded to the 100 th of a second and the two trials were averaged for
best time and recorded. Tethered maximal effort swim: Each subject completed
two in-water tethered maximal force generation swims (Digital
Force Gauge, IMADA, Inc). Each subject was instructed to go all out
from a push for 10 seconds. Maximal force generated was recorded in
Newton’s and the two trials averaged for best effort and recorded. Each
trial was separated by a minimum of 1 minute rest.
Resistance Training: Prior to the land testing each subject participated
in some light lifting for the benefit of warming up. Completion of the
two land strength tests was completed in randomized order. Bench Press:
Subjects completed a standard barbell chest press to determine a one
repetition maximum (1RM). The following protocol was established.
Each subject began with a warm up set consisting of light weight for
10-15 repetitions. Subjects then completed a set of moderate weight for
10 repetitions followed by a minimum of 2 minutes rest. The weight was
increased by 10-20 % and another set of 10 repetitions was completed.
This procedure was continued until the subject was unable to complete
ten full repetitions. 1RM BP was estimated using the following equation
(Brzycki 1993): Lifting weight (in pounds) / (1.0278-(.0278 x no.
of reps)). Leg Press: To establish a 1RM LP, subjects completed a bilateral
seated leg press following the same established protocol (Brzycki
1993) that was used for the 1RM BP.
Descriptive statistics (mean and SD) were calculated for subjects
characteristics (age, height, and weight). Pearson’s product moment correlation
coefficient (r) was used to explore the relationships among different
variables. The level of significance was set at p ≤ 0.01.
results
Table 1 summarizes the correlation coefficients for each of the variables
measured. A significant correlation was found to exist between BP
strength and both the TeS and the 22.9m swim respectively (r = 0.82 &
0.84). The relationship between BP and TeS and between BP and 22.9m
swim time is shown in figures 1 and 2 respectively.
The correlation between LP and the 22.9-m swim time was not as
strong as the BP (r = 0.70). In addition, no significant correlation existed
between LP and TeS force generated. However, further analyses revealed
that when the males were separated from the females, significant
correlations were found between all variables measured in both testing
sessions including LP vs TeS (Table 1).
Table 1. Mid season r-values for correlation between land strength and
in-water force generation measurements. P < 0.01; BP bench press, LP
leg press, 25 22.9-m swim, TeS tethered swim. Bold indicates significant
correlation.
Correlation Combined Males Females
LP vs 25 0.702409 0.752053 0.232553
LPrel vs 25 0.279929
LP vs TeS 0.504378 0.708448 0.282953
LPrel vs TeS 0.0782
BP vs TeS 0.819576 0.732068 0.560393
BPrel vs TeS 0.694141
BP vs 25 0.841623 0.871575 0.387719
BPrel vs 25 0.813758
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