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10 or 30-s sprint interval training bouts enhance both aerobic and anaerobic performance

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Abstract

We assessed whether 10-s sprint interval training (SIT) bouts with 2 or 4 min recovery periods can improve aerobic and anaerobic performance. Subjects (n = 48) were assigned to one of four groups [exercise time (s):recovery time (min)]: (1) 30:4, (2) 10:4, (3) 10:2 or (4) control (no training). Training was cycling 3 week(-1) for 2 weeks (starting with 4 bouts session(-1), increasing 1 bout every 2 sessions, 6 total). Pre- and post-training measures included: VO(2max), 5-km time trial (TT), and a 30-s Wingate test. All groups were similar pre-training and the control group did not change over time. The 10-s groups trained at a higher intensity demonstrated by greater (P < 0.05) reproducibility of peak (10:4 = 96%; 10:2 = 95% vs. 30:4 = 89%), average (10:4 = 84%; 10:2 = 82% vs. 30:4 = 58%), and minimum power (10:4 = 73%; 10:2 = 69%; vs. 30:4 = 40%) within each session while the 30:4 group performed ~2X (P < 0.05) the total work session(-1) (83-124 kJ, 4-6 bouts) versus 10:4 (38-58 kJ); 10:2 (39-59 kJ). Training increased TT performance (P < 0.05) in the 30:4 (5.2%), 10:4 (3.5%), and 10:2 (3.0%) groups. VO(2max) increased in the 30:4 (9.3%) and 10:4 (9.2%), but not the 10:2 group. Wingate peak power kg(-1) increased (P < 0.05) in the 30:4 (9.5%), 10:4 (8.5%), and 10:2 (4.2%). Average Wingate power kg(-1) increased (P < 0.05) in the 30:4 (12.1%) and 10:4 (6.5%) groups. These data indicate that 10-s (with either 2 or 4 min recovery) and 30-s SIT bouts are effective for increasing anaerobic and aerobic performance.
ORIGINAL ARTICLE
10 or 30-s sprint interval training bouts enhance both aerobic
and anaerobic performance
Tom J. Hazell Rebecca E. K. MacPherson
Braden M. R. Gravelle Peter W. R. Lemon
Accepted: 1 April 2010
Springer-Verlag 2010
Abstract We assessed whether 10-s sprint interval
training (SIT) bouts with 2 or 4 min recovery periods can
improve aerobic and anaerobic performance. Subjects
(n=48) were assigned to one of four groups [exercise
time (s):recovery time (min)]: (1) 30:4, (2) 10:4, (3) 10:2 or
(4) control (no training). Training was cycling 3 week
-1
for 2 weeks (starting with 4 bouts session
-1
, increasing 1
bout every 2 sessions, 6 total). Pre- and post-training
measures included: VO
2max
, 5-km time trial (TT), and a
30-s Wingate test. All groups were similar pre-training and
the control group did not change over time. The 10-s
groups trained at a higher intensity demonstrated by greater
(P\0.05) reproducibility of peak (10:4 =96%; 10:2 =
95% vs. 30:4 =89%), average (10:4 =84%; 10:2 =82%
vs. 30:4 =58%), and minimum power (10:4 =73%;
10:2 =69%; vs. 30:4 =40%) within each session while
the 30:4 group performed *2X(P\0.05) the total
work session
-1
(83–124 kJ, 4–6 bouts) versus 10:4 (38–
58 kJ); 10:2 (39–59 kJ). Training increased TT perfor-
mance (P\0.05) in the 30:4 (5.2%), 10:4 (3.5%), and
10:2 (3.0%) groups. VO
2max
increased in the 30:4 (9.3%)
and 10:4 (9.2%), but not the 10:2 group. Wingate peak
power kg
-1
increased (P\0.05) in the 30:4 (9.5%), 10:4
(8.5%), and 10:2 (4.2%). Average Wingate power kg
-1
increased (P\0.05) in the 30:4 (12.1%) and 10:4 (6.5%)
groups. These data indicate that 10-s (with either 2 or 4 min
recovery) and 30-s SIT bouts are effective for increasing
anaerobic and aerobic performance.
Keywords Endurance training Cycling VO
2max
Time trial Wingate
Introduction
Recently, a novel type of high-intensity interval training
known as sprint interval training (SIT; 4–6 repeated
‘all-out’ 30-s efforts separated by 4 min recovery) has
demonstrated increases in VO
2max
and aerobic performance
(2–30-km time trials; Burgomaster et al. 2006,2007;
Gibala et al. 2006). Apparently, the repeated SIT bouts
stress many of the physiological/biochemical systems used
in aerobic efforts (Daniels and Scardina 1984; Laursen and
Jenkins 2002). Further, SIT also induces alterations in
glycolytic enzymes, muscle buffering, and ionic regulation
resulting in improved anaerobic performance (Burgomaster
et al. 2005,2006,2007; Gibala et al. 2006; Harmer et al.
2000; MacDougall et al. 1998; Stathis et al. 1994).
Individual SIT bouts are characterized by a peak power
output in the first 5–10 s followed by a precipitous decline
over the remaining 20–25 s. Although clearly these kinds
of efforts represent a powerful training stimulus, whether
the mechanism responsible is the first 10 s (generation of
peak power), the entire 30 s (attempted maintenance of a
high power output), or the length of the recovery period
Communicated by Susan Ward.
T. J. Hazell (&)R. E. K. MacPherson
B. M. R. Gravelle P. W. R. Lemon
Exercise Nutrition Research Laboratory,
Faculty of Health Sciences, School of Kinesiology,
2235 3M Centre, The University of Western Ontario,
London, ON N6A 3K7, Canada
e-mail: thazell@uwo.ca
R. E. K. MacPherson
e-mail: rmacpher@uwo.ca
B. M. R. Gravelle
e-mail: bgravell@uwo.ca
P. W. R. Lemon
e-mail: plemon@uwo.ca
123
Eur J Appl Physiol
DOI 10.1007/s00421-010-1474-y
between repeats is unclear. Therefore, the purpose of this
study was to compare the established, effective SIT pro-
tocol (30 s ‘all-out’ efforts with 4 min recovery) versus
two modified types of SIT (10 s ‘all-out’ efforts with
either 4 min or 2 min recovery) on both aerobic and
anaerobic performance. We hypothesized that the peak
power generation is most important and, therefore, the 10 s
efforts would be effective.
Methods
Subjects
Forty-eight young adults (26 kinesiology students, 19
ultimate Frisbee players, and 3 other physically active
individuals; 35 men and 13 women) volunteered to par-
ticipate (24 ±3.2 years, 173 ±9.3 cm, 74 ±13.7 kg,
17 ±8.1% body fat, 47 ±6.7 ml kg
-1
min
-1
). Prior to
any participation, the experimental procedures and poten-
tial risks were explained fully to the subjects and all pro-
vided written informed consent. They were healthy as
assessed by the PAR-Q health questionnaire (Thomas et al.
1992) and, although all were physically active, none were
currently involved in an exercise training program nor had
they been for at least 4 months prior to the study. Dietary
and physical activity patterns were maintained throughout
the study and no alcohol, caffeine, or exercise was allowed
for 24 h before each testing or training session. Participants
were matched into four groups based on the sex, time trial
performance, and VO
2max
. This study was approved by the
University of Western Ontario Ethics Committee for
Research on Human Subjects.
Study design
Participants completed 2-weeks of cycle training (3 ses-
sion week
-1
) in one of the three SIT groups while the
control group did not train. Pre- and post- the 2 week
intervention, each completed tests for body composition,
VO
2max
, anaerobic power (30-s Wingate), and 5-km cycling
time trial performance (see details below). All tests were
separated by at least 24 h and to standardize recovery, post-
testing occurred within 72–96 h of the final training
session.
Pre-experimental procedures
Prior to any baseline testing, all participants attended a
laboratory familiarization visit to introduce the testing/
training procedures and also to ensure that any learning
effect was minimal for the baseline measures.
Baseline testing
All exercise tests were performed at the same time of day
on separate days, separated by at least 24 h, and at least
24 h prior to any training. Baseline testing was performed
in the same order for all subjects and consisted of four
measures.
1. VO
2max
test: An incremental test to exhaustion on an
electronically braked cycle ergometer (Ergo-metrics
800 s, SensorMedics, CA, USA) was utilized to
determine VO
2max
using an online breath by breath
gas collection system (Vmax Legacy, Sensor Medics,
CA, USA). Briefly, following a 5 min warm-up at
50 W, the test began at a workload of 20 W with the
workload increasing 25 W every minute for males
(5 W every 12 s) and 20 W every minute for females
(5 W every 15 s). VO
2max
was taken as the highest
value averaged over 30-s collection periods; 43 of 48
subjects reached a plateau in VO
2
(\50% of the
expected increase for the workload). The other five
subjects attained a max HR [91% of the age
predicted max (190 ±8 bpm), an RER [1.1, and a
VO
2
increase of 65–95% of predicted for the increase
in workload. Prior to testing, the analyzers were
calibrated with gases of known concentration and
volumes with a 3-l syringe.
2. 5-km time trial: A 5-km time trial on a customized
cycle ergometer interfaced with a computerized,
virtual road race course (CompuTrainer
) was used
to assess exercise performance. Participants received
instantaneous feedback throughout the 5-km race via a
computer video image of themselves and a competitor
programmed to complete their baseline performance.
In addition to the video images of both riders, previous
best time, time elapsed, current speed, and distance
ahead/behind (m) of the competitor was available on
the monitor. This feedback was provided to ensure
maximum motivation for the entire time trial. The time
trial was completed on three separate occasions prior
to any training to minimize learning and/or the effect
of day to day variability. The mean of the two fastest
efforts was used as the baseline performance time.
3. Wingate anaerobic cycle test: A 30-s Wingate anaer-
obic cycle test using a mechanically braked cycle
ergometer (model 814E bicycle ergometer, Monark,
Stockholm, Sweden) against a resistance equaling
100 g kg
-1
body mass. Instructions to begin pedaling
as fast as possible against the inertial resistance of the
ergometer were given and the appropriate load was
applied instantaneously (within 3 s). Verbal encour-
agement was provided for the remainder of the 30-s
test. Peak power (highest power output over any 5-s
Eur J Appl Physiol
123
period) and average power (over the entire effort) were
determined using an online data-acquisition system
(Monark Wingate Ergometer Test, Monark Body
Guard, AB, Version 1.0).
4. Body composition analysis: Body composition (lean
mass and fat mass) was determined by whole body
densitometry (BodPod
, Life Measurements, Concord,
CA) as previously described (Dempster and Aitkens
1995; Noreen and Lemon 2006). Briefly, participants
wore approved clothing, i.e., tight swimsuit or com-
pression shorts, Lycra
cap, and for the women, a
sports bra, were weighed, sat in an air tight chamber
for several determinations, a predictive equation
integral to the BodPod
software was used to estimate
thoracic gas volume, and the attained value for body
density was used in the Siri equation to estimate body
composition (Siri 1961).
Training
After the baseline procedures, participants were assigned to
one of the three training groups (30-s exercise:4 min
recovery, 10 s:4 min, 10 s:2 min) or the control group (C)
based on their time trial performance, VO
2max
, and sex.
Training commenced *48 h after their third baseline
performance test and consisted of three training sessions
per week over 2 weeks with 48–72 h recovery between
training sessions. All training was completed using a load
of 100 g kg body mass
-1
.
Group 30 s:4 min: Performed repeated, 30 s ‘all-out’
efforts separated by 4 min of active recovery (unloaded
cycling) similar to previous studies (Burgomaster et al.
2008; Gibala et al. 2006).
Group 10 s:4 min: Performed repeated, 10 s ‘all-out’
efforts separated by 4 min of active recovery (unloaded
cycling).
Group 10 s:2 min: Performed repeated, 10 s ‘all-out’
efforts separated by 2 min of active recovery (unloaded
cycling).
Training progression was accomplished by increasing
the number of repeats from four repetitions during the first
two training sessions, to five repetitions during the middle
two training sessions, and then to six repetitions for the
final two training sessions as has been done previously
(Gibala et al. 2006).
Reproducibility of power measures within a training
session
To quantify the training intensity of each group the peak
power output of each sprint bout per training session were
summed, averaged, divided by the greatest peak power
output during all training sessions and expressed as a percent
([peak power 1 ?peak power 2 ?peak power 3 ?peak
power 6/6]/highest peak 9100). Similarly, average and
minimum power output during the training sessions were
determined for all groups. Finally, total work performed
during each training session was calculated (average power
output 9time) for all three training groups.
Post-training testing
Post-training measures were identical to the baseline testing
and completed within 48–96 h after the final training session.
Statistics
Statistical analyses were performed using Sigma Stat for
Windows (Version 3.5). After testing for normality and
variance homogeneity, two-way (treatment 9time) repe-
ated measures ANOVA were used to test significance
among groups pre- and post-training, with Tukey’s post
hoc testing, where necessary. One-way ANOVA were also
used to test for significant differences in training intensities
(reproducibility of peak power output, average power
output, and total work output) among groups. The signifi-
cance level was set at P\0.05. All data are presented as
mean ±standard deviation (SD).
Results
Time trial
The 5-km cycling time trial was completed in approxi-
mately 9.5 min for all groups at baseline (P=0.620). All
three training groups improved their time trial performance
significantly over the 2-weeks of exercise (Fig. 1);
30 s:4 min improved by 5.2% (-28.9 s; P\0.001),
10 s:4 min by 3.5% (-19.8 s; P=0.003), and 10 s:2 min
group by 3.0% (-15.7 s; P=0.022). None of these per-
formance gains were significantly different among training
groups. As expected, the control group showed no change
(from 588 ±118 to 587 ±116 s; P=0.862).
VO
2max
There was no significant difference in the baseline values
among groups (P=0.627) but there was a significant inter-
action with time (training group versus time; P=0.015;
Fig. 2). VO
2max
increased 9.3% (4.3 ml kg
-1
min
-1
;P\
0.001) in the 30 s:4 min group and 9.2%(4.5 ml kg
-1
min
-1
;
P\0.001) in the 10 s:4 min group. In the 10 s:2 min group,
the increase in VO
2max
approached statistical significance
Eur J Appl Physiol
123
(3.8%; 1.8 ml kg
-1
min
-1
;P=0.06). There were no sig-
nificant differences among training groups. The control
group showed no change in VO
2max
(from 45.2 ±4.6 to
45.3 ±3.5 ml kg
-1
min
-1
;P=0.899).
Relative peak power output
There was no significant difference in baseline relative peak
power output among groups (P=0.437), but there was a
significant interaction with time (training group vs. time;
P=0.017; Fig. 3). The 30 s:4 min group increased 9.5%
(1.3 W kg
-1
;P\0.001), the 10 s:4 min group increased
8.5% (1.3 W kg
-1
;P\0.001) while the 10 s:2 min group
improved 4.2% (0.6 W kg
-1
;P=0.029). None of these
observed group gains were significantly different from each
other. The control group showed no change (14.2 ±1.9 to
14.2 ±1.6 W kg
-1
;P=0.959).
Relative average power output
Baseline relative average power output values were similar
among groups (P=0.383) and there was a significant
interaction with time (training group vs. time; P=0.002;
Fig. 4). The 30 s:4 min group improved 12.1% (1.0 W kg
-1
;
P\0.001) and the 10 s:4 min group increased 6.5%
(0.6 W kg
-1
;P=0.003). The observed increase in the
10 s:2 min group (2.9%; 0.3 W kg
-1
) failed to reach
statistical significance (P=0.136). None of these changes
were significantly different from each other. Again, the
control group showed no change (9.5 ±1.2 to 9.3 ±
1.1 W kg
-1
;P=0.510).
Reproducibility of power outputs during training
sessions
There was a significant difference in the ability of the
training groups to maintain peak power output during the
training sessions (P\0.001; Fig. 5). The 10 s:4 min
group maintained 96% of their peak power output and the
10 s:2 min group 95% which were both significantly
greater (P\0.001) than the 89% observed for the
30 s:4 min group.
5 km Time Trial Performance (sec)
0
450
500
550
600
650
700
750
800
850
900
** **
02 weeks
02 weeks
02 weeks
02 weeks
30:4 10:4 10:2 CONTROL
Fig. 1 5-km cycling time trial performance (s) before and after
2 weeks of training. Thin lines are individual data and the thick lines
are means. All training groups improved significantly while the
control group did not change. **P\0.001, *P\0.03
0
25
30
35
40
45
50
55
60
65
70
VO
2
max (ml•kg
-1
•min
-1
)
**
**
02 weeks
02 weeks
02 weeks
02 weeks
30:4 10:4 10:2 CONTROL
Fig. 2 VO
2max
(ml kg
-1
min
-1
) before and after 2 weeks of training.
Thin lines represent individual data and the thick lines are means.
Both the 30:4 and 10:4 training groups improved significantly while
the 10:2 approached significance. The control group did not change.
**P\0.001,
P=0.06
Relative Peak Power Output (W·kg
-1
)
0
10
12
14
16
18
20
** ** *
02 weeks
02 weeks
02 weeks
02 weeks
30:4 10 :4 10:2 CON TROL
Fig. 3 Wingate relative peak power output (W kg
-1
) before and after
2 weeks of training. Thin lines are individual data and the thick lines
are means. All training groups improved significantly while the
control group did not change. **P\0.001, *P\0.03
Eur J Appl Physiol
123
Similarly, there was a significant difference in the ability
of the training groups to maintain average power output
during training sessions (P\0.001; Fig. 5). The
10 s:4 min group and 10 s:2 min group maintained 84 and
82% of their peak power output, respectively, which were
both significantly greater (P\0.001) than the 58%
observed for the 30 s:4 min group.
As with both peak and average power output, there was
a significant difference in the minimum power output
observed during the training sessions (P\0.001; Fig. 5).
Minimum power output for the 10 s:4 min group and
10 s:2 min group was 73 and 69% of their peak power
output, respectively. Both were significantly greater
(P\0.001) than the 40% for the 30 s:4 min group.
Total work performed also differed among training
groups (P=0.005). As expected, the 30 s:4 min group
(83–124 kJ) performed significantly more total work
(P\0.009) during the 4–6 bouts per training session than
either the 10 s:4 min group (38–58 kJ) or the 10 s:2 min
group (39–59 kJ). There was no difference in total work
performed between the 10 s:4 min and the 10 s:2 min
groups (P=0.999).
Body composition
Baseline values for body composition (body mass, lean
mass, fat mass, body fat percentage) were similar among
groups (P[0.430). Training did not cause changes in
body composition (P[0.490) and, as expected, there were
no body composition changes in the control group
(PC0.626).
Discussion
Recent studies utilizing SIT (repeated maximal 30-s efforts
with 4 min recovery) have reported significant increases in
both anaerobic and aerobic power (Gibala and McGee
2008). Increases in glycolytic (MacDougall et al. 1998) and
oxidative enzymes activity (Burgomaster et al. 2005,2006,
2007; MacDougall et al. 1998), muscle buffering capacity
(Burgomaster et al. 2007; Gibala et al. 2006), and/or ionic
regulation (Harmer et al. 2000) have been implicated in
these responses. Moreover, it has been demonstrated
that SIT up-regulates peroxisome proliferator-activated
receptor-co-activator-1a(PGC-1a), a potent regulator of
mitochondrial biogenesis (Burgomaster et al. 2008; Gibala
et al. 2009), which could be the underlying mechanism
responsible for the observed aerobic adaptation. This
information is exciting because it means that such adap-
tations can be obtained with a substantial reduction
in exercise training time. Consequently, many types of
athletes and perhaps even non-athletes interested in being
physically active for health reasons can benefit from this
novel type of training. However, not much is known
regarding which particular aspect of SIT provides this
powerful stimulus. The purpose of the current study was to
determine whether the observed improvements in anaero-
bic and aerobic performance are due to the generation of
peak power output, the total work completed over 30 s,
and/or the brief recovery interval. If the peak power output
generation is most important we would expect that the
two-10 s treatments would produce similar or greater
Relative Average Power Output (W·kg
-1
)
0
5
6
7
8
9
10
11
12
** *
02 weeks
02 weeks
02 weeks
02 weeks
30:4 10:4 10: 2 CONTROL
Fig. 4 Wingate relative average power output (W kg
-1
) before and
after 2 weeks of training. Thin lines are individual data and the thick
lines are means. Both the 30:4 and 10:4 training groups improved
significantly while the 10:2 and the control group did not change.
**P\0.001, *P\0.03
40
60
80
100
40
60
80
100
Training Session
Peak Power
Output (%)
Training Session
Average Power
Output (%)
Training Session
Minumum Power
Output (%)
**
**
**
30 :4 1 0: 4 10 :2 30:4 10:4 10:2 30:4 10:4 10:2
Fig. 5 Reproducibility of peak, average, and minimum power during
the training sessions. The 30 s:4 min maintained significantly less
peak, average, and minimum power than the 10 s:4 min and
10 s:2 min training groups. Data are mean ±SD. **P\0.001
Eur J Appl Physiol
123
improvements versus the 30 s protocol because, of course,
the peak power occurs during the first 5 or 10 s of SIT. On
the other hand, if the average power output (or total work
completed) over the 30 s is critical then the 30-s treatment
should be best. Finally, if the intersession recovery interval
is a key factor then the 2–10 s treatments (with 2 vs. 4 min
recovery interval) should produce different results.
Our results demonstrate that both modified SIT proto-
cols (10 s:4 min and 10 s:2 min) produced similar and
significant VO
2max
and 5-km time trial performance
improvements when compared with the established
30 s:4 min SIT protocol. This suggests that the generation
of peak power output during the first few seconds of each
training bout is more likely responsible for the SIT adap-
tations than the total work completed.
As expected, the training session peak power genera-
tion (% of peak power over each training repeat) was
more reproducible (P\0.05) with both 10-s groups
versus the 30-s group (96 and 95 vs. 89%). Further, both
average power (84, 82 vs. 58%) and minimum power
(73, 69 vs. 40%) over each training repeat were greater
(P\0.05) with the 10-s groups versus the 30 s. As a
result, the 10-s groups did *50% of the work completed
in the 30-s group in only 33% of the training time. In
other words, the 10-s groups exercised for less time, but
at greater exercise intensity. Finally, although we did not
quantify the effort involved, subjectively the participants
appeared to find the 10 s efforts less difficult and their
comments during training were consistent with this
possibility. Taken together, these data suggest that,
although the 30 s:4 min SIT is very time efficient versus
more traditional endurance training, significant perfor-
mance gains are possible with an even smaller time
commitment. This may be very useful for athletes who
need to boost their performance over the course of their
competitive season when fitness might suffer due to
increased emphasis on skill development.
The observed improvements in time trial performance
(3–5%), VO
2max
(4–9%), peak power output (9–10%), and
average power output (7–12%) are consistent with other
SIT studies utilizing the established 30 s:4 min protocol
(Barnett et al. 2004; Burgomaster et al. 2006,2007,2008;
Gibala et al. 2006; MacDougall et al. 1998; Stathis et al.
1994). Of course, these increases in both aerobic and
anaerobic power are likely responsible for the observed
improvements in time trial performance.
Some may be surprised by the aerobic adaptations
observed with such short exercise bouts, but when one
examines the response of the muscles involved with SIT
more closely our results are much more reasonable, even
expected. Specifically, the well-known precipitous decline
in peak power output during SIT type exercise is due to the
fall in muscle PCr stores primarily (Bogdanis et al. 1995,
1996). Further, the decrease in PCr availability combined
with the continued attempt to generate maximal power
should stimulate both glycolysis and oxidative phosphor-
ylation with the later becoming even more pronounced
during successive bouts (McCartney et al. 1986; Spriet
et al. 1989). Likely this coupling of PCr hydrolysis and
oxidative metabolism explains at least partially why both
the 10 and 30-s training efforts present a significant acute
challenge to the mitochondria resulting in adaptation. In
addition, about 50 years ago, Astrand et al. (1960a,b)
suggested that oxygen availability from myoglobin should
be reduced with continuous versus intermittent exercise at
the same relative intensity because with the latter it would
be reloaded during recovery. If so, the relative proportion
of energy regenerated from glycolysis and oxidative
phosphorylation would be altered with longer exercise
bouts even if the intensity was identical, i.e., more gly-
colysis with continuous exercise. This reloading of myo-
globin with oxygen phenomenon could also contribute to
the aerobic improvement observed with all three types of
SIT studied because 2–4 min of recovery should be plenty
of time to reload. Moreover, the unloading of myoglobin in
the 30-s SIT group would be expected to contribute to a
greater glycolytic involvement versus the 10-s groups.
Interestingly, although training increased Wingate peak
power output in all three SIT groups, average Wingate
power output tended to be greater with the 30 s:4 min
versus the 10 s:4 min group (11.4 vs. 7.6%) and was not
significantly increased with training in the 10 s:2 min
group (2.9%). This result is consistent with a greater reli-
ance on glycolysis during training in the 30-s group and
could explain at least partially why the more intense 10-s
repeats seemed less difficult.
With respect to recovery duration, our similar across
group performance gains over 2 weeks of training and
greater peak power reproducibility with training repeats in
the 10-s groups indicate that two min of recovery is
sufficient for the next ‘‘all-out’’ effort. From a practical
perspective, this suggests that total training time can be
reduced versus even 30 s:4 min SIT without compromising
training adaptations. In this study, we did not test 30-s
efforts with 2 min recovery and this should be assessed to
be certain that intensity can be maintained in subsequent
bouts. However, 50% reduction in recovery time might
also be appropriate with 30-s SIT because despite the larger
oxygen debt incurred versus 10-s efforts we have observed
that VO
2
recovers consistently by *80% as quickly as
120 s following a typical SIT session (4 repeat 30-s efforts;
unpublished observations). Perhaps, the incomplete
recoveries which characterize SIT contribute to the aerobic
adaptation of the muscle because it is forced to regenerate
energy at a very high rate with a decreasing anaerobic
contribution (Barnett et al. 2004).
Eur J Appl Physiol
123
The results of the current study agree with earlier work
demonstrating the effectiveness of 30 s:4 min SIT relative
to aerobic and anaerobic adaptations. However, of sub-
stantial interest is our observation that many of the same
performance gains occurred in our two modified SIT pro-
tocols, 10-s efforts with either 2 or 4 min recovery in which
actual time exercising was reduced by 67% and, for the
10 s:2 min group, recovery time was reduced by another
50%. This means that for the 10 s:2 min group training
total time would be as little as \7–11 versus 14–
23 min day
-1
for 30 s:4 min or 30–60 min day
-1
for
traditional continuous endurance training. As a result SIT
should be easily incorporated into the training program of
any athlete desiring to increase both aerobic and anaerobic
power quickly. However, it is still unclear how these
modified 10-s SIT protocols would compare to traditional
ET over longer training programs. Moreover, at least over
2 weeks SIT had no effect on body composition in these
recreationally active young individuals so longer training
durations are needed to determine the effectiveness of these
SIT protocols on body composition.
Recently, interval training for non-athletes, even those
with compromised cardiovascular function has been utilized
with considerable success (Rognmo et al. 2004; Warburton
et al. 2005; Wisloff et al. 2007), but it is important to
appreciate that SIT is considerably more intense. Conse-
quently, before SIT is adopted widely by non-athletes more
study is necessary to determine whether there are health
concerns with this type of training in other populations.
Conclusion
The present study demonstrates that SIT protocols using
4–6 repetitions of 10-s duration with 2 or 4 min of
recovery, three times per week over as brief a time period
as 2 weeks can increase VO
2max
, peak Wingate power
output, and 5-km cycle time trial performance. While the
underlying mechanism responsible for these rapid adapta-
tions must await further study the fact that bouts of 10-s
were as effective as 30-s suggests that the main stimulus of
SIT is the generation of peak power output.
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... 8,9 Particularly, several SIT protocols with repeated short (≤10 s) efforts (sSIT) were shown to exhibit similar aerobic and anaerobic adaptations but better perceptual and enjoyment responses (i.e., "less pain, same gain") than Wingate-based SIT. [10][11][12][13] The greater efficiency of these sSIT protocols is related to the fact that the highest mechanical responses are achieved during the first seconds of sprinting bouts, 9 while the reduced glycolytic activity would result in less peripheral fatigue 14 because of the more reliance on the ATP-PCr pathway during the first 10 s of effort 15 Moreover, the acute responses of different sSIT schemes have been described with respect to physical, 10,14 physiological, 10,16,17 and perceptual 10,12 responses. However, there are only a few recent studies examining the physical and physiological adaptations after a number of sessions over only a few weeks, in cycling and running sprints with promising results. ...
... The meta-analysis included a total of 438 participants, of whom 239 performed supervised sSIT, 107 participants performed no exercise or no additional sSIT, 49 performed HIIT as control condition, 45 performed other SIT modality as control condition, and 13 performed CT as control condition. Of the included studies, cycling was the most common mode of exercise (8 studies), 13,19,[33][34][35][36][37][38] followed by running (6 studies). 11,[39][40][41][42][43] Additionally, boxing exercise, 44 canoe paddling, 45 functional fitness exercises, 46 handcycling, 47 and squatting + cycling 19 were also assessed by one study each. ...
... 11,[39][40][41][42][43] Additionally, boxing exercise, 44 canoe paddling, 45 functional fitness exercises, 46 handcycling, 47 and squatting + cycling 19 were also assessed by one study each. In 12 of the included studies, sSIT was performed at maximal possible intensity ("all-out"), 11,13,19,34,37,38,40,41,[44][45][46][47] while 5 studies assessed the effect of non-"all-out" high-intensity efforts, 33,36,39,42,43 and one study gave no further description about the intensity. 35 ...
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... Authors reported that both 6 and 30 s all-out SIT training elicited similar changes in performance. Another study, comparing two 10 s (with 2 and 4 recovery intervals min) and a 30 s SIT exercises, showed that all three of the SIT protocols increased oxidative and anaerobic performance [13]. ...
... SIT protocols with different recovery periods elicited similar increase in VO 2max [11,13]. ...
... Olek et al. [11] reported similar VO 2max improvements after 2 weeks SIT period (3 sessions a week, 6 sessions in total) in two different SIT training groups (W:R; 10:60 s; 10:240 s). Similarly, Hazel et al. [13] showed that 2-weeks SIT protocols with different recovery intervals (10 s all-out run with either 120 s or 240 s rest) induced similar increase in VO 2max . The results of the present study showed similar VO 2max improvements both in SIT150 and SIT30 training groups. ...
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The objective of the present study was to investigate the selected performance adaptations of amateur soccer players to 2 different running-based sprint interval training (SIT) protocols with different recovery intervals and work-rest ratios (1:5 & 1:1). Twenty-three subjects (age 21.4±1.1 years; height 175.4±4.7 cm; body mass 69±6.4 kg) participated in the study. Before the 6-weeks training period, participants completed 3-weeks of low-intensity training preparation. Subsequently, the pre-tests (anthropometric measurements, repeated sprint test [12×20-m with 30-s recovery intervals], Yo-YoIRT1 & Yo-YoIRT2 and treadmill VO2max test) were conducted. Thereafter, participants were randomly divided into 3 sub-groups (1 – SIT with 150 s recovery intervals [SIT150, n = 8]; 2 – SIT with 30 s recovery intervals [SIT30, n = 7]; and 3 – control group [CG, n = 8]). SIT150 and SIT30 training groups completed sprint interval training (2-days/week; 30-s all-out running, 6–10 repetition with 150 s recovery intervals for SIT150 and 30 s for SIT30 groups, respectively), a soccer match (1-day) and routine soccer training (3-days) per week. The CG attended only routine training sessions and the soccer-match (4-days). The study experiments and the trainings were conducted during off-season. Yo-YoIRT1, Yo-YoIRT2, and VO2max were significantly improved both in SIT30 and SIT150 (p < 0.05) groups. Yo-YoIRT1 and VO2max were also significantly improved in CG (p < 0.05). Both the SIT150 and SIT30 training were shown to improve Yo-YoIRT1, Yo-YoIRT2 and VO2max performance compared to the control group, nevertheless, SIT150 was more efficient in improving the Yo-YoIRT1, Yo-YoIRT2 than SIT30. The authors of this study suggest using SIT150 to induce more effective performance outputs in amateur soccer players.
... Interval exercise is a time-efficient style of training involving repeated bouts of relatively intense exercise interspersed by short periods of active or passive recovery. Studies have shown that high-intensity interval exercise (HIIE) can improve cycling performance (Hazell et al., 2010), cardiorespiratory fitness (Hazell et al., 2010;Astorino et al., 2011), and body composition (Hazell et al., 2014). Current terminology defines HIIE as 'near maximal' repeated efforts performed at intensities between 85 and 95% of maximal heart rate and sprint interval exercise (SIE) as efforts performed at maximal or supramaximal intensities (Hazell et al., 2010;Gillen et al., 2014;MacInnis and Gibala, 2017;Wood et al., 2016). ...
... Interval exercise is a time-efficient style of training involving repeated bouts of relatively intense exercise interspersed by short periods of active or passive recovery. Studies have shown that high-intensity interval exercise (HIIE) can improve cycling performance (Hazell et al., 2010), cardiorespiratory fitness (Hazell et al., 2010;Astorino et al., 2011), and body composition (Hazell et al., 2014). Current terminology defines HIIE as 'near maximal' repeated efforts performed at intensities between 85 and 95% of maximal heart rate and sprint interval exercise (SIE) as efforts performed at maximal or supramaximal intensities (Hazell et al., 2010;Gillen et al., 2014;MacInnis and Gibala, 2017;Wood et al., 2016). ...
... Studies have shown that high-intensity interval exercise (HIIE) can improve cycling performance (Hazell et al., 2010), cardiorespiratory fitness (Hazell et al., 2010;Astorino et al., 2011), and body composition (Hazell et al., 2014). Current terminology defines HIIE as 'near maximal' repeated efforts performed at intensities between 85 and 95% of maximal heart rate and sprint interval exercise (SIE) as efforts performed at maximal or supramaximal intensities (Hazell et al., 2010;Gillen et al., 2014;MacInnis and Gibala, 2017;Wood et al., 2016). In comparison, moderate intensity continuous exercise (MICE) is defined as exercise performed in a continuous fashion at lower intensities than those used during interval training (MacInnis and Gibala, 2017). ...
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The purpose of this investigation was to compare changes in circulating lymphocyte subset cell counts between high-intensity interval exercise (HIIE), sprint interval exercise (SIE), and moderate-intensity continuous exercise (MICE). Recreationally active men (n = 11; age: 23 ± 4 yr; height: 179.9 ± 4.5 cm; body mass: 79.8 ± 8.7 kg; body fat %:12.6 ± 3.8%; V̇O2max: 46.6 ± 3.9 ml⋅kg⁻¹⋅min⁻¹) completed a maximal graded exercise test to determine maximal oxygen uptake (V̇O2max) and three duration-matched cycling trials (HIIE, SIE, and MICE) in a randomized, counterbalanced fashion. HIIE consisted of fifteen 90-s bouts at 85% V̇O2max interspersed with 90-s active recovery periods. SIE consisted of fifteen 20-s bouts at 130% maximal power and 160-s active recovery periods. MICE was a continuous bout at 65% V̇O2max. Total exercise duration was 53 min in all three trials, including warm-up and cool-down. Blood was collected before, immediately post, 30 min, 2 h, 6 h, and 24 h post-exercise. Changes in lymphocyte subset counts, and surface expression of various markers were analyzed via flow cytometry. Changes were assessed using mixed model regression analysis with an autoregressive first order repeated measures correction. Significant decreases were observed in absolute counts of CD56dim NK cells, CD19⁺ B cells, CD4⁺ T cells, and CD8⁺ T cells 30 min and 24-h post-exercise in all three trials. Despite resulting in greater total work and oxygen consumption, MICE elicited similar changes in lymphocyte subset counts and receptor expression compared to both SIE and HIIE. Similarly, while the two interval trials resulted in differing oxygen consumption and total work, no differences in the lymphocyte response were observed. Though both forms of exercise resulted in declines in circulating lymphocyte cell counts, neither exercise type provides an immune-related advantage when matched for duration.
... A duration of 30 s is conventionally used in sprint training, with the first 5-10 s representing the period during which peak power is achieved, with the latter 20-25 s constituting an effort to maintain this output [18]. Hazell and colleagues (2010), when comparing 10 s and 30 s sprint protocols, suggested that the initial generation of peak power output (PPO) was likely responsible for sprint interval training adaptations [19]. Sprint training is primarily dependent on the ability to match ATP resynthesis rate to utilization rate and altered intracellular and extracellular ion concentrations [12]. ...
... Athletes were able to maintain their PPO, independent of the training session. This is congruent with the literature, which suggests that PPO is generated during the first 5-10 s of exertion [19,23]. Thus, athletes would have had time to reach their maximal power output even during the short-duration sprint protocol. ...
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... However, as discusses in his book, "The One Minute Workout", the key ingredient to HIIT's effectiveness is the intensity level of the working bouts as well as the change in intensity. Gibala is referencing evidence found from the experiment completed by Hazell, MacPherson, Gravelle, and Lemon (2010). In this study, two HIIT protocols were compared, one with 10-second working bouts and one with 30-second bouts. ...
... Allerdings wurden in verschiedenen wissenschaftlichen Studien die Wirksamkeit einer wiederholten Ausführung zum Trainingszweck sowie die Auswirkungen auf ausgewählte physiologische Parameter untersucht. Dabei kam der WAnT vier-, fünf-oder teilweise sechsmal zur Anwendung (Greer et al., 1998;Hazell et al., 2010). Auch beim Tretwiderstand sind verschiedene Variationen der Testdurchführung möglich. ...
Thesis
Full-text available
High-intensity interval training, characterized by repetitive short to long bouts of high-intensity exercise separated by recovery periods, represents a time-efficient training methodology for improving athlete performance. Previous research indicates that physiological and anatomical differences in men and women may result in divergences in training response. Furthermore, the state of research suggests that changes in skeletal muscle and different functional systems over the course of age may induce different responses to an exercise stimulus. In this regard, the results show that there is a sexual dimorphism in load and recovery during interval exercise. Furthermore, it was found that good trainability is possible in old age, which in turn may counteract age-related changes and their influence on load and recovery behavior.
... Intensität zwischen 90 und 95 % der HRmax als wirksam erwiesen (Helgerud et al. 2001;Helgerud et al. 2007;Impellizzeri et al. 2006). Aber auch verschiedene andere Varianten mit Intervalldauern von 10 s (sehr hohe Intensität und kurze Pausen) bis zu 8 min (geringere Intensität bei längeren Pausen) können verschiedene Indikatoren der Leistungsfähigkeit steigern (Burgomaster et al. 2008;Gibala et al. 2006;Iaia et al. 2009;Hazell et al., 2010;Schmitz et al., 2017;Schmitz et al., 2018c). ...
Thesis
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