Acute and delayed effects of high-intensity interval resistance training organization on cortisol and testosterone production

Abstract

The use of high--intensity interval training (HIIT) is widely diffused as strategy to enhance aerobic fitness and body composition. In order to offer a more complete training, resistance exercises have been added to HIIT (HIIRT). Aims of our study were to characterize both heart rate and hormonal responses elicited by three different protocols of HIIRT having the same exercises, the same load and number of repetitions for each exercise.

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ACUTE AND DELAYED EFFECTS OF HIGH INTENSITY INTERVAL RESISTANCE
TRAINING ORGANIZATION ON CORTISOL AND TESTOSTERONE PRODUCTION –
Di Blasio et al. - ©The Journal of Sports Medicine and Physical Fitness
!
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ACUTE AND DELAYED EFFECTS OF HIGH INTENSITY INTERVAL RESISTANCE
TRAINING ORGANIZATION ON CORTISOL AND TESTOSTERONE PRODUCTION –
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!
ACUTE AND DELAYED EFFECTS OF HIGH INTENSITY INTERVAL RESISTANCE
TRAINING ORGANIZATION ON CORTISOL AND TESTOSTERONE PRODUCTION
Andrea Di Blasio1 *
Pascal Izzicupo2
Laura Tacconi1
Serena Di Santo1
Marina Leogrande1
Ines Bucci1
Patrizio Ripari3
Angela Di Baldassarre2
Giorgio Napolitano1
1Endocrine Section, Department of Medicine and Aging Sciences, ‘G. d’Annunzio’
University of Chieti–Pescara, Italy
2Human Morphology Section, Department of Medicine and Aging Sciences, ‘G. d’Annunzio’
University of Chieti–Pescara, Italy
3Department of Clinical and Experimental Sciences, ‘G. d’Annunzio’ University of Chieti–
Pescara, Italy

ACUTE AND DELAYED EFFECTS OF HIGH INTENSITY INTERVAL RESISTANCE
TRAINING ORGANIZATION ON CORTISOL AND TESTOSTERONE PRODUCTION –
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Acknowledgements: the authors are grateful to Iris Puca, M.Sc., B.Sc., and to Sportacademy
Fitness Centre for their scientific and technical support.
*Corresponding author: Andrea Di Blasio
Department of Medicine and Aging Sciences
c/o University Centre of Sports Medicine
“G. d’Annunzio” University of Chieti–Pescara
Viale Abruzzo 322, 66013 Chieti Scalo, Italy
Tel: +39-0871-587107; Fax: +39-0871-574936
e-mail: andiblasio@gmail.com

ACUTE AND DELAYED EFFECTS OF HIGH INTENSITY INTERVAL RESISTANCE
TRAINING ORGANIZATION ON CORTISOL AND TESTOSTERONE PRODUCTION –
Di Blasio et al. - ©The Journal of Sports Medicine and Physical Fitness
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Abstract
Aim. The use of high-intensity interval training (HIIT) is widely diffused as strategy to
enhance aerobic fitness and body composition. In order to offer a more complete training,
resistance exercises have been added to HIIT (HIIRT). Aims of our study were to characterize
both heart rate and hormonal responses elicited by three different protocols of HIIRT having
the same exercises, the same load and number of repetitions for each exercise.
Methods. Eight healthy trained men (28.61 ±3.51 yrs) performed three different workouts:
exercise order, recovery and speed of execution were differently organized according to
workout. Salivary samples were collected before and after each workout, at 11:00 p.m. and at
7:00 a.m. of the following day. Salive was also collected during a non-training day. Before
and after the workout, plasma lactate was measured while a beat-to-beat heart rate recording
was executed during each workout. Cortisol (C) and testosterone (T) were measured in
salivary samples.
Results. Workouts elicited the same heart rate response while random organization seems to
elicit the highest lactate, C and T increases. Also when we studied the effects of workouts on
prolonged hormones production we observed that workout organization influenced post-
exercise hormonal production until the following morning modifying their physiological
trend.
Conclusions. Even if exercises, load and number of repetitions were maintained fixed,
exercise order, structured recovery and speed of execution determined different acute and
prolonged effects. The knowledge of these responses is very important because may
positively or negatively influence performance and health.

ACUTE AND DELAYED EFFECTS OF HIGH INTENSITY INTERVAL RESISTANCE
TRAINING ORGANIZATION ON CORTISOL AND TESTOSTERONE PRODUCTION –
Di Blasio et al. - ©The Journal of Sports Medicine and Physical Fitness
!
Key words: steroid hormones, lactate, workout organization

ACUTE AND DELAYED EFFECTS OF HIGH INTENSITY INTERVAL RESISTANCE
TRAINING ORGANIZATION ON CORTISOL AND TESTOSTERONE PRODUCTION –
Di Blasio et al. - ©The Journal of Sports Medicine and Physical Fitness
!
Introduction
Literature reports growing evidence about the effectiveness of the high-intensity interval
training (HIIT) on the improvement of aerobic fitness and body composition [1], but also on
treatment of pathological conditions, such as metabolic and cardiovascular diseases, as
alternative method to traditional endurance training [2]. High-intensity interval training is
practical for many individuals due to the minimal time commitment required when compared
to traditional continuous endurance training; indeed, HIIT is characterized by high intensity
sessions, that can range anywhere from 5 or 10 seconds to 5 or 10 minutes, interspersed by
periods of recovery, which modality (i.e. active or passive recovery) and duration can vary
according to the target [3]. Therefore, high intensity has also a negative side, because, when
the method is applied to pathological people, it is necessary a careful evaluation,
programmation and control to avoid negative effects on health. Also when it is applied to
healthy people it is necessary to pay attention; indeed, a correct periodization avoids negative
consequences, of excessive load, on cardiovascular, muskoloskeletal, endocrine and immune
systems [4, 5]. As to improve and maintanin health, but also to adeguately train an athlete, it
is important to train metabolic pathways and both cardiovascular and respiratory systems [6,
7], but also resistance training and flexibility; HIIT should include also resistance training and
flexibility to give a complete intervention. So, a relatively new variation of HIIT has recently
become popular and incorporates high intensity intervalled resistance exercises (HIIRT) using
varied, multiple joint movements. As HIIRT has recently become popular worldwide,
literature about this argument is poor and varied. Indeed, even if Smith and colleagues [8]
furnished first data about the effectiveness of HIIRT to significantly increase maximal aerobic
capacity and decrease body fat, both in men and women, independently from the initial
fitness; Bergeron and colleagues [9] underlined the increased injury risk among HIIRT

ACUTE AND DELAYED EFFECTS OF HIGH INTENSITY INTERVAL RESISTANCE
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participants while Taro and colleagues [10] investigated the nature and prevalence of injuries.
As the principal characteristic of HIIRT is the high intensity, that can be modulated changing
the number of repetition, the load, and the speed of execution of each exercise, but also
intervening on total duration of the session, duration and intensity of recovery, and as
literature lacks in heart rate and hormonal characterization of a HIIRT session, aims of our
study were to characterize both heart rate and hormonal responses elicited by three different
protocols of HIIRT having the same exercises, the same load and number of repetitions for
each exercise.
Materials and methods
Participants
Eight healthy non-smokers trained men (28.61 ±3.51 yrs) were recruited and
participated to the study completing it. Subjects were recruited at the SportAcademy Fitness
Centre (Pescara, Italy) among the costumers who were free from any diseases and were
accustomed with the experimented workouts and functional movements. All of the subjects
provided written informed consent. The research was conducted respecting the ethical
principles of the Declaration of Helsinki.
Study design
All participants underwent a careful clinical examination, anthropometry, body
composition assessment, and preliminary endurance and resistance testing before the
execution of the experimental workouts. Then, each workout was tested in a different week,

ACUTE AND DELAYED EFFECTS OF HIGH INTENSITY INTERVAL RESISTANCE
TRAINING ORGANIZATION ON CORTISOL AND TESTOSTERONE PRODUCTION –
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while two resting days anticipated and followed the testing days. At each workout, a battery
of measurements and withdrawals was applied to detect endocrine and cardiac responses
elicited by the workout. Two exercise specialists supervised each workout. During all the
phases of study, the laboratory conditions were controlled for temperature (21–23 °C) and
humidity (50%) [11].
Clinical examination, anthropometry and body composition
Clinical examination was executed by a medical doctor specialized in sports medicine
to exclude any diseases. A first level anthropometrist of the International Society for the
Advancement of Kinanthropometry measured body weight and stretched stature and
performed electrical bioimpedance analysis according to international guidelines [11-12]. A
stadiometer with a balance-beam scale (Seca 220, Seca, Hamburg, Germany) and a foot-to-
foot 50 kHz frequency bioelectrical impedance scale (BC-420MA, Tanita, Tokyo, Japan)
were used.
Preliminary testing
Preliminary testing for endurance exercises included the assessment of subjects’
maximal heart rate through a graded stress test (i.e. Bruce protocol) on a treadmill (770 CE,
RAM, Padua, Italy), under continuous electrocardiogram monitoring and step-by-step blood
pressure measurements [11]. The graded stress test was also used to confirm the
cardiovascular eligibility of each participant. Preliminary testing for resistance exercises
included the determination of the maximum number of repetitions for each of the following
exercises, in the following order: kettlebell swing, medicine ball slam, spin with Bulgarian
bag, squat, pull-up, burpee. The weight of kettlebell, medicine ball and Bulgarian bag varied

ACUTE AND DELAYED EFFECTS OF HIGH INTENSITY INTERVAL RESISTANCE
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by participant to participant: each participant chose weights allowing a fluent movement and
maintained them during the study. For each exercise, we firstly recorded the maximum
number of repetitions that each participant was able to do in 10 seconds (MR10sec). Then,
after a complete recovery, subjects executed the exercise at a cadence of 80% of MR10sec
while an exercise specialist recorded number of repetitions and controlled the movement.
When the movement was incorrect, it was not included in the count and the participant was
advised about that; when the cadence was failed for two consecutive times, the exercise was
stopped and total number of repetitions was considered as maximum. After complete
recovery, all exercises were tested according to the order above described. As participants had
different muscular fitness, in order to be sure that each participant exercised according to his
muscular fitness, the Spartan workout volume [13], a popular workout chosen by people
practicing CrossFit, was used as reference parameter to calculate total repetitions of each
exercise and total repetitions of workouts according to preliminary testing results (i.e.
resistance testing). Table 1 shows how total repetitions of workouts and repetitions of each
exercise have been calculated.
Measurements and withdrawals
Participants, that always trained at the same hour, presented in the gym at 6:30 p.m.
and started the training, 2.5 hours after a standardized meal, at 7:00 p.m., without having
performed maximal muscle exertion, sexual intercourses, and abstaining from stimulants and
alcohol from 2 days before to the experimental days and until 9:00 a.m. of the following day.
The meal was lower to 400 kcal [14] and consisted of 33 cl of water, 35 cl of orange juice and
two 30 g energy bars (Power Sport Double Use, Enervit, Milan, Italy). Before to start each
workout, in a standardized room [11], each subject wore a Polar RS800CX (Polar, Kempele,

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Finland), settled at beat-to-beat modality, to record heart rate during the training. After that, a
salivary sample was collected using Salimetrics Oral Swab (Salimetrics Europe, Suffolk,
UK), while blood lactate was measured, using finger capillary blood sample, through
Accutrend Plus and BM-Lactate test strips (Roche, Basel, Switzerland). Before to start the
workout, each participant did a standardized warm-up of 10 minutes under the supervision of
the exercise specialists. After the warm-up the Polar RS800CX was initialized and the
workout started; at the end of the workout the heart rate monitor was stopped. Within one
minute from the end of the workout, blood lactate was re-measured and salivary sample was
re-collected. Salivary sample was also collected at 11:00 p.m. of the same day and at 7:00
a.m. of the day following the workout. Participant avoided stimulants and alcohol intake
during the experimental days and avoided food intake during the 2 hours before each
collection. Each participant recorded the dinner of the first workout they experimented in
order to have the same dinner at each experimental day. We did not furnish indication about
the quantity, that was ad libitum.
In order to better determine the delayed workout-elicited endocrine responses, salivary
samples were also collected during a non-training (CONTROL) day, respecting the same
standardization used for training days collections. CONTROL day salivary collections were
executed at 7:00 p.m., 11:00 p.m. and at 7:00 a.m. of the following day.
Analytical methods
Salivary samples were collected using Salimetrics Oral Swab (Salimetrics Europe,
Suffolk, UK), i.e. a small pad, absorbent and non-toxic, passed within the oral cavity for 2-3
minutes before being placed inside a tube labeled. The samples were refrigerated within 30
minutes and frozen at -20° C within 2 hours of collection. The day of the assay, samples were

ACUTE AND DELAYED EFFECTS OF HIGH INTENSITY INTERVAL RESISTANCE
TRAINING ORGANIZATION ON CORTISOL AND TESTOSTERONE PRODUCTION –
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!
thawed and centrifuged for 15 minutes at 3,000 rpm to extract saliva and remove the mucin
and the swab was then discarded. The assays were performed using the following salivary
assay kits: Salivary Testosterone EIA kit and High Sensitivity Salivary Cortisol EIA Kit
(Salimetrics Europe, Suffolk, UK).
Experimental workouts: characteristics
For each participant, the tested workouts were characterized by the same exercises, by
the same repetitions of each exercise, by the same total repetitions (i.e. sum of repetitions of
each exercise) but by a different organization.
RANDOM workout: the assigned goal was to complete the assigned repetitions
respecting only two duties. The first one was don’t stop until all of the repetitions were
completed; the second was that there were no assigned order of execution of exercises and no
assigned consecutive repetitions to complete. Participants were free to choose both the order
of exercises and number of consecutive repetitions for each exercise (i.e. 2 repetitions of
kettlebell swing, 10 repetitions of medicine ball slam, 20 repetitions of squat, 4 repetitions of
spin with Bulgarian bag, etc.). No recovery period was assigned, except the time necessary to
move from a station to another, and no speed of execution of exercises was assigned:
participants were free to choose the preferred speed.
LADDER workout: respecting the following order of execution, kettlebell swing,
medicine ball slam, spin with Bulgarian bag, squat, pull-up, burpee, participants had to
complete the total repetitions according to a pyramidal scheme (e.g. 1st lap 10 repetitions at
each exercise, 2nd lap 9 repetitions at each exercise) until the total number of repetitions of
each exercise was executed. Each lap of the circuit was followed by 1 minute of recovery. No

ACUTE AND DELAYED EFFECTS OF HIGH INTENSITY INTERVAL RESISTANCE
TRAINING ORGANIZATION ON CORTISOL AND TESTOSTERONE PRODUCTION –
Di Blasio et al. - ©The Journal of Sports Medicine and Physical Fitness
!
speed of execution of exercises was assigned: participants were free to choose the preferred
speed.
AS SOON AS POSSIBLE (ASAP) workout: respecting the following order of
execution, kettlebel swing, medicine ball slam, spin with Bulgarian bag, squat, pull-up,
burpee, participants had to complete the total volume in six laps executed as soon as possible.
During each lap participants had to complete the sixth part of total number of repetitions of
each exercise without rest among exercises. Each lap of the circuit was followed by 1 minute
of recovery.
Statistical analysis
The STATA 10 software (StataCorp LP, College Station, USA) was used for
statistical analysis. The data were tested for normality and are presented as means ±standard
deviations also when non-parametric tests were performed, to give the possibility to the
readers to know the value of each variable. The Kruskal-Wallis Test was used to compare pre-
workouts hormonal values and heart rate distribution, among different intensities (i.e. time
elapsed at different intensities), according to workout participation. The Kruskal-Wallis Test
and the analysis of covariance were used to verify whether workouts elicited a different acute
hormonal and lactate variations and whether they were linked with their basal values. Acute
hormonal and lactate variations were calculated subtracting post-workout hormonal and
lactate values to their pre-workout corresponding. In order to know whether the experimented
workouts had prolonged effects on cortisol (C) and testosterone (T) production (i.e. until the
morning following the training) and whether the workouts elicited a significant variation of
their physiological trend, and obviously of the physiological trend of their ratio, analysis of
variance, with repeated measures for the factor ‘time’ (RM-ANOVA), was used to investigate

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the presence of group, time, or group × time effect on hormones production. RM-ANOVA
was performed comparing the values recorded during training days + following morning with
those recorded during CONTROL day + following morning. The values recorded at 7:00
p.m., 11:00 p.m. and at 7:00 a.m. of the following day were used in the analysis. Statistical
significance was set at p ≤0.05.
Results
Table 2 shows basal characteristics of participants, while Table 3 shows the
comparison of both pre-workouts hormonal values and distribution of the recorded heart rate
among different intensities. Pre-workouts lactate, C, T and cortisol to testosterone (C to T)
ratio were different among the three exercise protocols that did not differ for duration.
According to the results presented in Table 3, protocols elicited the same heart rate response:
the major part of each workout was spent between 80 and 100% of maximal heart rate,
confirming the high cardiovascular intensity of the workouts.
As showed in Table 4, workouts elicit different hormonal and lactate variations:
LADDER workout seems to elicit the lowest lactate increase, while RANDOM workout
seems to elicit the highest lactate, C and T increases. When C was considered in ratio with T
no significant differences have been shown among workouts-induced variations. Results of
the analysis of covariance, executed on significantly modified variables, confirmed that basal
hormonal and lactate values did not influence their variations (Table 5). When we studied the
effects of workouts on prolonged hormones production (i.e. until the morning following the
training) which were also compared with their physiological trend (i.e. CONTROL days), we
observed that C had both time (F=179.723; p<0.001) and group × time effect (F=10.942;
p<0.001): while during non-training day there is a physiological decline of C production at

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11:00 p.m., during training days its decline is not present but seems to have a continuous
increase from 7:00 p.m. to 7:00 a.m. (Figure 1). Also for T production we observed the
presence of both time (F=443.340; p<0.001) and group × time effect (F=3.254; p=0.008) even
if the group × time effect seems determined by the samples collected at 7:00 p.m. and this is
not due to workout (Figure 1). When we consider the C to T ratio we observed the presence of
both time (F=127.924; p<0.001) and group × time effect (F=8.655; p<0.001): workouts elicit
a different trend of the ratio, from 7:00 p.m. to 7:00 a.m. of the following day, respect to that
recorded during CONTROL days. It seems that workouts elicit the increase of the ratio from
7:00 p.m. to 11:00 p.m. instead of its physiological decline (Figure 1).
Discussion
The starting point of our discussion is the analysis of results concerning workouts
duration and heart rate distribution among different intensities: no significant differences
among workouts. Independently from exercises organization, the experimented workouts are
important stimulus for the cardiovascular system, even if exercises are not executed as soon
as possible. This is probably due to the big total volume of muscle masses involved during the
workouts; indeed, even if participants did not train with maximal loads, the major part of the
chosen exercises was almost total body and was characterized by high number of multi-joint
movements. This means that the cardiovascular system is engaged to sustain the work of a
total big volume of muscle masses. The absence of significant differences among workouts, in
duration and heart rate distribution among different intensities, and the absence of significant
effects of basal lactate and hormonal values on their variation (Table 5) allow detecting the
pure effect of practice organization on lactate and hormonal responses, as duration and
intensity of the training have been shown important influencing factors of both C and T

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responses to exercise [15].
Analyzing the effects of workouts on lactate production, we observed that LADDER
workout elicits the lowest increase of lactate while RANDOM workout the highest. We can
use the LADDER workout as control to interpret and explain the observed results: indeed, its
pyramid scheme, the exercise order (i.e. alternation of predominant upper-body exercise with
predominant lower-body exercise) and the presence of 1 minute of recovery, after each lap of
the circuit, theoretically allowed the lowest lactate increase. The pyramid scheme,
characterized by the reduction of exercise repetitions, at each lap, without increasing the
external load, did, at each lap, a reduced work, so a reduced energy request. The alternation of
predominant upper-body exercises with predominant lower-body exercises probably allowed
lactate clearance; indeed, the end of the training for a muscle group is linked with a reduction
of constrictive forces, mechanically limiting muscle circulation and lactate efflux from
training muscles into the blood [16]. Adding that, the observed alternation acts like a local
active recovery [17], indeed it allowed a little recovery in trained muscles meanwhile other
muscles are working. In addition, the 1 min of recovery, executed at the end of each lap, is
additionally useful to partially reduce blood lactate and restore muscles energetic substrates
[18]. As consequence, the absence of a structured recovery and the absence of a structured
exercise order and number of consecutive repetitions, for each exercise, could be the cause of
the highest lactate increase recorded for RANDOM workout. As lactate production has been
shown closely linked with both C and T increase, through direct and/or exercise-mediated
patterns [15, 19] also their highest increase, recorded after RANDOM workout, could be
explained by the same causes: by the absence of a structured recovery and by the absence of a
structured exercise order and number of consecutive repetitions, for each exercise. As
consequence, it is logical to deem that if participants would spontaneously adopt a scheme

ACUTE AND DELAYED EFFECTS OF HIGH INTENSITY INTERVAL RESISTANCE
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similar to LADDER workout, even in the absence of a structured recovery, they would have a
lower lactate and hormonal increase. Therefore, further studies are needed to experimentally
verify if the conclusion of our reasoning is right or a speculation.
When we analyzed the effects of workouts on prolonged hormones production (i.e.
until the morning following to the training) we observed that our workouts differently
modified the physiological trend of both C and C to T ratio of participants (Figure 1). Indeed,
RANDOM workout elicited the highest acute hormonal and lactate response (Table 4) and the
lowest catabolic effects at 11:00 p.m. together with CONTROL day, while LADDER and
ASAP workouts have been shown able to determine higher ascent trend of both salivary C
and C to T ratio (from 7:00 p.m. to 11:00 p.m.) respect to RANDOM workout and respect to
CONTROL day, eliciting, on the contrary, their descent trend. As showed by Sgrò and
colleagues [20], the prolonged effects of different workouts on the investigated hormones
seem to be principally due to their effects on C production. Indeed, even if the parallel
increase of C and T, observed immediately after the workouts, seems to exclude the presence
of a rapid inhibitory effect of C on T secretion, the absence of significant differences on
salivary T at 11:00 p.m. (Figure 1) could represent a late inhibitory effect of C on T
production having the same magnitude of their increase. This delayed decrease of T is
explained in literature by inhibitory effect of C on luteinizing hormone production rate [21].
This could mean that the metabolic prolonged effect of the experimented HIIRT protocols is
influenced by their impact on C production, regulating the catabolic/anabolic state. Intense
exercise leads to C elevations, persisting for a few hours after cessation of exercise, and
constituting an adequate reaction to the energetic, metabolic, anti-inflammatory, and vascular
demands of exercise [22]. Indeed, the stress imposed by high-volume muscular contractions
and high intensity training causes energy depletion requiring an energetic restoration achieved

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through high C to T ratio, determining increased fat and decreased carbohydrate utilization.
As HIIRT protocols also determine muscles damages, for the repeated muscular contractions,
late high C to T ratio is important for its anti-inflammatory effect while muscular regeneration
processes are protected, in trained individuals, by the reduction of glucocorticoids sensitivity
from 8 to 24 hours after exercise [22]. This decreased sensitivity occurs as a beneficial
adaptation to protect muscle and other tissues against glucocorticoids when the catabolic or
anti-inflammatory actions of the steroids are no longer needed. Interesting to note is the fact
that even if at 11:00 p.m. salivary C and C to T ratio were higher during training days; at 7:00
a.m., salivary C and C to T ratio were higher if the day prior to the sampling participants did
not train. These results suggest that the experimented workouts, when practiced on late
afternoon, are able to modulate the time course of C production and its physiological morning
C increase. Indeed, according to workout characteristics, it is possible to elicit higher night
and lower morning catabolic state, respect to a CONTROL day (Figure 1). This is probably
due to a negative feedback inhibition, to further protect body tissues from excessive
exposition to a catabolic state, even if morning C increase is a physiological condition [23].
The small sample size is the main limitation of the study, therefore, the observed
results must be considered not as a statement but as a starting point for further studies
including higher sample size. Therefore, the fact that the study was conducted on a group of
expert participants and that each participant executed all of the experimented workouts is
strength and can partially compensate the small sample size. Another limitation of the study is
the absence of a completely controlled diet, even if, maintaining the ad libitum principle,
standardizing pre-workout meal and demanding to participants to eat the same dinner, at each
experimental day, could be sufficient to completely exclude the presence of dietary habits
influences on our results.

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Conclusions
In conclusion, HIIRT, independently from the exercises order, the speed of their
execution, the presence of structured recovery, and from the use of maximal loads is
characterized by high cardiovascular engagement. On the contrary, the different organization
of the same exercise characteristics in an HIIRT elicits different acute and prolonged effects
on C and T production even if workouts did not differ for duration and cardiovascular
intensity. The knowledge of these concepts is very important because the stimulation of the
right balance between hypothalamic-pituitary-testicular and hypothalamic-pituitary-adrenal
axes, through physical exercise, including also the proper dietary and recovery period, may
positively or negatively influence many peripheral tissue and systems favouring or inhibiting
performance and health.
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ACUTE AND DELAYED EFFECTS OF HIGH INTENSITY INTERVAL RESISTANCE
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TITLES OF TABLES
Table 1. Determination of individual total repetitions and repetitions of each exercise.
Table 2. Basal characteristics of participants.
Table 3. Comparisons of pre-workout hormone levels and distribution of the recorded heart
rates among the different exercise protocols.
Note: Random w., Random workout; Ladder w., Ladder workout; ASAP w., As Soon As
Possible workout; HR, heart rate; t, time; WD%, percentage of workout duration.
Table 4. Comparisons of hormonal and lactate variations.
Note: Random w., Random workout; Ladder w., Ladder workout; ASAP w., As Soon As
Possible workout; ∆, post-workout minus pre-workout value
Table 5. Analysis of covariance. Effects of lactate and hormonal basal levels on their post-
workouts variations.

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TRAINING ORGANIZATION ON CORTISOL AND TESTOSTERONE PRODUCTION –
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Table 1. Determination of individual total repetitions and repetitions of each exercise.
Total repetitions recorded during the
preliminary testing
Sum of the repetitions recorded at 6 exercises
(∑6 ex.)
Individual total repetitions
(∑6 ex. × 300)/ (mean ∑6 ex. of participants)
Kettlebell swing
(individual total repetitions × 55) / 300
Medicine ball slan
(individual total repetitions × 55) / 300
Spin with Bulgarian bag
(individual total repetitions × 55) / 300
Squat
(individual total repetitions × 55) / 300
Pull-up
(individual total repetitions × 25) / 300
Burpee
(individual total repetitions × 55) / 300

ACUTE AND DELAYED EFFECTS OF HIGH INTENSITY INTERVAL RESISTANCE
TRAINING ORGANIZATION ON CORTISOL AND TESTOSTERONE PRODUCTION –
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Table 2. Basal characteristics of participants
Mean ±SD
N = 8
Age (yrs)
28.68 ±3.47
Body Mass Index (kg/m2)
23.87 ±2.41
Fat mass (%)
14.21 ±4.33
Measured maximal heart rate (bpm)
189.02 ±8.65
VO2max (ml/kg/min)
51.63 ±2.49
Kettlebell swing (rep)
27.77 ±11.11
Medicine ball slam (rep)
27.77 ±8.59
Spin with Bulgarian bag (rep)
34.88 ±8.26
Squat (rep)
56.11 ±8.20
Pull-up (rep)
8.22 ±4.99
Burpee (rep)
19.77 ±11.27

ACUTE AND DELAYED EFFECTS OF HIGH INTENSITY INTERVAL RESISTANCE
TRAINING ORGANIZATION ON CORTISOL AND TESTOSTERONE PRODUCTION –
Di Blasio et al. - ©The Journal of Sports Medicine and Physical Fitness
!
Table 3. Comparison of both pre-workouts hormonal values and distribution of the recorded
heart rate among different intensities.
Random w.
Ladder w.
ASAP w.
p
Cortisol (pg/ml)
1661.18
±441.90
728.75 ±224.27
1372.81
±322.65
0.001
Testosterone (pg/ml)
85.88 ±14.90
82 ±23.34
62.94 ±11.38
0.012
Cortisol to Testosterone
19.04 ±2.69
8.80 ±0.72
21.87 ±4.28
<0.001
Lactate (mmol/l)
1.41 ±0.33
2.82 ±0.47
2.32 ±0.23
<0.001
Workout duration (sec)
1330.67 ±93.03
1571.33
±276.17
1237.67
±142.46
0.252
Mean HR (bpm)
167.67 ±11.84
166.33 ±11.01
173.33 ±18.87
0.875
Max HR (bpm)
180 ±12.16
183.33 ±17.01
194 ±26.28
0.967
t ≤65% HRmax (WD%)
-
0.40 ±0.69
-
0.368
65 < t ≤70% HRmax (WD%)
0.33 ±0.57
0.76 ±0.66
1.16 ±1.10
0.332
70 < t ≤75% HRmax (WD%)
1.13 ±1.02
2.36 ±1.30
3.03 ±1.93
0.393
75 < t ≤80% HRmax (WD%)
3.03 ±1.70
11.96 ±7.69
9.23 ±8.66
0.329
80 < t ≤85% HRmax (WD%)
32.90 ±42.22
26.63 ±14.60
17.80 ±14.43
0.670
85 < t ≤90% HRmax (WD%)
28.06 ±30.08
32.33 ±14.90
31.76 ±25.98
0.957
90 < t ≤95% HRmax (WD%)
24.90 ±25.36
6.60 ±8
10.30 ±5.50
0.472
95 < t ≤100% HRmax (WD%)
9.70 ±16.80
11.73 ±20.32
4.20 ±7.27
0.939
100 < t ≤105% HRmax
(WD%)
-
6.56 ±11.37
10.63 ±18.41
0.558
105 < t ≤110% HRmax
-
0.06 ±0.11
9.40 ±16.28
0.558

ACUTE AND DELAYED EFFECTS OF HIGH INTENSITY INTERVAL RESISTANCE
TRAINING ORGANIZATION ON CORTISOL AND TESTOSTERONE PRODUCTION –
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(WD%)
Note: Random w., Random workout; Ladder w., Ladder workout; ASAP w., As Soon As
Possible workout; HR, heart rate; t, time; WD%, percentage of workout duration.

ACUTE AND DELAYED EFFECTS OF HIGH INTENSITY INTERVAL RESISTANCE
TRAINING ORGANIZATION ON CORTISOL AND TESTOSTERONE PRODUCTION –
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Table 4. Comparison of hormonal and lactate variations.
Random w.
Ladder w.
ASAP w.
p
∆Cortisol (pg/ml)
3616.93
±2176.38
1388.75
±663.50
1223.12
±837.56
0.004
∆Testosterone (pg/ml)
80.35 ±12.12
33.87 ±11.61
32.90 ±11.18
<0.001
∆Cortisol to ∆Testosterone
43.46 ±21.99
41.14 ±10.86
38.03 ±16.30
0.195
∆Lactate (mmol/l)
12.11 ±3.01
6.19 ±2.71
11.30 ±0.76
0.001
Note: Random w., Random workout; Ladder w., Ladder workout; ASAP w., As Soon As
Possible workout; ∆, post-workout minus pre-workout value

ACUTE AND DELAYED EFFECTS OF HIGH INTENSITY INTERVAL RESISTANCE
TRAINING ORGANIZATION ON CORTISOL AND TESTOSTERONE PRODUCTION –
Di Blasio et al. - ©The Journal of Sports Medicine and Physical Fitness
!
Table 5. Analysis of covariance. Effects of lactate and hormonal basal levels on their post-
workouts variations.
F
P
Lactate
Corrected model
9.777
<0.001
Intercept
5.130
0.035
Pre-workouts Lactate
0.700
0.413
Workouts
8.584
0.002
Cortisol
Corrected model
6.743
0.003
Intercept
0.001
0.974
Pre-workouts Cortisol
3.736
0.07
Workouts
4.306
0.02
Testosterone
Corrected model
28.681
<0.001
Intercept
11.602
0.003
Pre-workouts Testosterone
0.674
0.421
Workouts
35.666
<0.001

ACUTE AND DELAYED EFFECTS OF HIGH INTENSITY INTERVAL RESISTANCE
TRAINING ORGANIZATION ON CORTISOL AND TESTOSTERONE PRODUCTION –
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TITLE OF FIGURE
Figure 1. Hormonal trends.
Legend: continue line, RANDOM workout; dashed line, LADDER workout; dotted line,
ASAP workout; alternated dashed-dotted line, CONTROL day.