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Effects of protein–carbohydrate supplementation on immunity and resistance training outcomes: a double-blind, randomized, controlled clinical trial

  • Fundación Canaria Instituto de Investigación Sanitaria de Canarias

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PurposeTo examine the impact of ingesting hydrolyzed beef protein, whey protein, and carbohydrate on resistance training outcomes, body composition, muscle thickness, blood indices of health and salivary human neutrophil peptides (HNP1-3), as reference of humoral immunity followed an 8-week resistance training program in college athletes. Methods Twenty-seven recreationally physically active males and females (n = 9 per treatment) were randomly assigned to one of the three groups: hydrolyzed beef protein, whey protein, or non-protein isoenergetic carbohydrate. Treatment consisted of ingesting 20 g of supplement, mixed with orange juice, once a day immediately post-workout or before breakfast on non-training days. Measurements were performed pre- and post-intervention on total load (kg) lifted at the first and last workout, body composition (via plethysmography) vastus medialis thickness (mm) (via ultrasonography), and blood indices of health. Salivary HNP1-3 were determined before and after performing the first and last workout. ResultsSalivary concentration and secretion rates of the HNP1-3 decreased in the beef condition only from pre-first-workout (1.90 ± 0.83 μg/mL; 2.95 ± 2.83 μg/min, respectively) to pre-last-workout (0.92 ± 0.63 μg/mL, p = 0.025, d = 1.03; 0.76 ± 0.74 μg/min, p = 0.049, d = 0.95), and post-last-workout (0.95 ± 0.60 μg/mL, p = 0.032, d = 1.00; 0.59 ± 0.52 μg/min, p = 0.027, d = 1.02). No other significant differences between groups were observed. Conclusions Supplementation with a carbohydrate–protein beverage may support resistance training outcomes in a comparable way as the ingestion of only carbohydrate. Furthermore, the ingestion of 20 g of hydrolyzed beef protein resulted in a decreased level and secretion rates of the HNP1-3 from baseline with no negative effect on blood indices of health.
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Eur J Appl Physiol (2017) 117:267–277
DOI 10.1007/s00421-016-3520-x
Effects of protein–carbohydrate supplementation on immunity
and resistance training outcomes: a double‑blind, randomized,
controlled clinical trial
Fernando Naclerio1 · Eneko Larumbe‑Zabala2 · Nadia Ashrafi1 · Marco Seijo1 ·
Birthe Nielsen1 · Judith Allgrove3 · Conrad P. Earnest4
Received: 19 July 2016 / Accepted: 19 December 2016 / Published online: 27 December 2016
© The Author(s) 2016. This article is published with open access at
indices of health. Salivary HNP1-3 were determined before
and after performing the first and last workout.
Results Salivary concentration and secretion rates of the
HNP1-3 decreased in the beef condition only from pre-
first-workout (1.90 ± 0.83 μg/mL; 2.95 ± 2.83 μg/min,
respectively) to pre-last-workout (0.92 ± 0.63 μg/mL,
p = 0.025, d = 1.03; 0.76 ± 0.74 μg/min, p = 0.049,
d = 0.95), and post-last-workout (0.95 ± 0.60 μg/mL,
p = 0.032, d = 1.00; 0.59 ± 0.52 μg/min, p = 0.027,
d = 1.02). No other significant differences between groups
were observed.
Conclusions Supplementation with a carbohydrate–pro-
tein beverage may support resistance training outcomes in
a comparable way as the ingestion of only carbohydrate.
Furthermore, the ingestion of 20 g of hydrolyzed beef pro-
tein resulted in a decreased level and secretion rates of the
HNP1-3 from baseline with no negative effect on blood
indices of health.
Keywords Immune status · Strength performance · Body
composition · Muscle thickness · Blood indices of health
AST/GOT Alanine transaminase
AMP Antimicrobial peptides
ALT/GPT Aspartate transaminase
BM Body mass
CHO Carbohydrate
CK Creatine kinase
DHEA Dehydroepiandrosterone
Generalized eta squared
HDL High density lipoprotein
HNP1-3 Human neutrophil peptides
LDL Low density lipoprotein
ANOVA One-way analysis of variance
Purpose To examine the impact of ingesting hydrolyzed
beef protein, whey protein, and carbohydrate on resistance
training outcomes, body composition, muscle thickness,
blood indices of health and salivary human neutrophil pep-
tides (HNP1-3), as reference of humoral immunity followed
an 8-week resistance training program in college athletes.
Methods Twenty-seven recreationally physically active males
and females (n = 9 per treatment) were randomly assigned
to one of the three groups: hydrolyzed beef protein, whey
protein, or non-protein isoenergetic carbohydrate. Treatment
consisted of ingesting 20 g of supplement, mixed with orange
juice, once a day immediately post-workout or before break-
fast on non-training days. Measurements were performed pre-
and post-intervention on total load (kg) lifted at the first and
last workout, body composition (via plethysmography) vastus
medialis thickness (mm) (via ultrasonography), and blood
Communicated by William J. Kraemer.
Electronic supplementary material The online version of this
article (doi:10.1007/s00421-016-3520-x) contains supplementary
material, which is available to authorized users.
* Fernando Naclerio
1 Department of Life and Sports Sciences, University
of Greenwich, Chatham Maritime, UK
2 Clinical Research Institute, Texas Tech University Health
Sciences Center, Lubbock, TX, USA
3 Faculty of Science Engineering and Computing, Kingston
University, London, UK
4 Exercise Science and Nutrition Laboratory, Texas A&M
University, College Station, TX, USA
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268 Eur J Appl Physiol (2017) 117:267–277
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Heavy exercise can lead to significant transient perturba-
tions in immune functions (Walsh et al. 2011b). In ath-
letes, the so-called immunosuppression has been associ-
ated with a weakened immune state lasting for up to 72 h
after performing a strenuous exercise session (Nieman and
Bishop 2006). Consequently, different nutritional strate-
gies, including the combination of carbohydrates with
high-quality protein sources, ingested throughout the day
(Jones et al. 2015) or during and after workouts or com-
petitions (Naclerio et al. 2015), have been proposed as an
effective nutritional countermeasure to exercise-induced
immune dysfunction with no detrimental effects on indices
of health (e.g., blood chemistry measures) (Antonio et al.
2016). Furthermore, adding protein to augment resistance
training outcomes is supported by their capacity to rap-
idly increase amino acid availability to the working mus-
cles (Wilkinson et al. 2007). Specifically, the post-workout
consumption of high-quality proteins would shift the bal-
ance in favor of muscle anabolism (Rennie et al. 2004) and,
as a consequence, acts to maximize recovery and training
effects between workouts (Morton et al. 2015).
Whey and beef protein extracts are high-quality pro-
tein sources with a similar amino acid composition to that
found in the skeletal muscles (Chernoff 2004; Cruzat et al.
2014). Either whey and beef protein sources include sulfur-
containing amino acids, such as cysteine and methionine or
taurine that have been associated with an efficient immune
status (Reidy and Rasmussen 2016). As a consequence, it
could be possible to hypothesize that the ingestion of high-
quality protein extracts via the provision of an amino acid
would support the immune response in individuals engaged
in exhaustive and intense exercise programs.
Defensins, including alpha-defensins, are antimicro-
bial peptides (AMP) contributing to mucosal host defense
providing a broad spectrum of antibacterial and antifungal
activity (Wang 2014). The alpha-defensins also known as
human neutrophil peptides (mainly HNP1-3) are predomi-
nantly found in neutrophils. Within the last 15 years, sev-
eral investigations have analyzed the response of these
salivary markers of humoral immunology in various oral
and systemic diseases (Yount and Yeaman 2012). Although
some studies have investigated the impact of exercise on
humoral immunity (Gleeson 2000), to the best of authors
knowledge only two studies have analyzed the HNP1-3
response to exercise (Davison et al. 2009; Gillum et al.
2015) and neither of which have investigated the impact of
combining nutritional supplements on the long-term adap-
tation of humoral immunity. Davison et al. (2009) reported
an acute increase in the absolute concentration of the sali-
vary AMP (HNP1-3 and LL-37) in participants having
performed a 2.5 h cycling intervention at 60% of VO2max
while Gillum et al. (2015) observed an acute increase in
the level of four AMP (LL-37, HNP1-3, LL-37, L Lacto-
ferrin, and Lysozyme) in participants after 45 min of run-
ning at 75% VO2peak. The post-exercise increase of salivary
AMP may to some extent be related to an exercise-induced
muscle inflammatory response (Davison et al. 2009). Extra-
neous dynamic exercise may induce airway inflammation
and damage to airway epithelial cell (Davison et al. 2009).
Thus, interventions aimed to analyze long-term adapta-
tion on the humoral immunity without side effects on the
general health would be of relevant importance for ath-
letes. The aim of the current investigation was to compare
the effectiveness of combining an 8-week resistance train-
ing program with a commercially available beef hydro-
lyzed protein powder product, whey isolate or a non-pro-
tein, carbohydrate only supplement on resistance training
outcomes. The primary outcome for the study was sali-
vary alpha-defensins (HNP1-3) and secondary outcomes
included performance, body composition, muscle thick-
ness, and various blood indices of health.
Forty-two recreationally active college participants (24
male and 18 females) met the requirements to participate
in this study. Key criteria for inclusion were: (a) 18–40 year
of age, (b) regular recreationally training for at least 2 years
with a minimum of 1 month performing resistance train-
ing, (c) free from musculoskeletal limitations, (d) agree
not to ingest any other nutritional supplements or non-
prescription drugs or medication that might affect the
immune system or muscle growth as well as the ability to
train intensely during the study, and (e) fluent in English.
Key criteria used for exclusion were: (a) history of various
metabolic conditions and/or diseases; (b) use of a variety of
medications, including but not limited to those with andro-
genic and/or anabolic effects and/or nutritional supple-
ments known to improve strength and/or muscle mass such
as creatine, essential amino acid, whey protein, glutamine,
dehydroepiandrosterone (DHEA) within 8 weeks prior to
the beginning of the study; (d) current use of tobacco prod-
ucts; and/or in the case of female participants ingesting
oral contraceptives; and (e) the presence of any orthopedic
limitations or injuries. Compliance was confirmed verbally
with participants upon arrival to the laboratory.
All participants were informed of the potential risks
of the intervention before agreeing to comply with the
intervention protocol and signed an informed consent.
All experimental procedures were conducted in accord-
ance with the Declaration of Helsinki, and approved by
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269Eur J Appl Physiol (2017) 117:267–277
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the University ethics committee. As summarized in Fig. 1,
after assessing for eligibility, 27 of the 42 recruited par-
ticipants completed all aspects of the study. The study
was conducted during the spring and summer of 2015 at
the Centre for Science and Medicine in Sport and Exercise
University of Greenwich Medway Campus, Kent (UK).
Trial Registration:, U.S. National Insti-
tutes of Health. (Identifier: NCT02425020) on 22nd April
Experimental design
This study was a randomized controlled trial with three
parallel groups, following a double blind between-partic-
ipant design. Participants were randomly allocated into
three treatment groups: beef protein (n = 14); whey pro-
tein (n = 14) or carbohydrate only (CHO, n = 14). Before
(test 1) and after (test 2) an 8-week intervention period,
measurements of performance, body composition and mus-
cular thickness, total cholesterol, low density lipoprotein
(LDL) and high density lipoprotein (HDL) cholesterol,
triglycerides, glucose, urea, uric acid, creatine kinase (CK),
creatinine, alanine transaminase (AST/GOT), aspartate
transaminase (ALT/GPT) and HNP1-3 salivary immune-
peptides were assessed. Additionally, saliva was collected
before and after the first and the last workout of the 8-week
intervention protocol.
After inclusion and before the baseline assessment, par-
ticipants performed six sessions of familiarization, aimed
to minimize any potential learning effects of the training
procedures. Following the pre-intervention assessments,
participants were matched by gender and resistance train-
ing background. Assignment of participants to treatments
was performed by block randomization, using a block
size of three, and in a double-blind fashion. Initial groups
characteristics were as follows: beef: age 25.6 ± 5.7 years,
height 1.72 ± 0.09 m, body mass 74.2 ± 17.3 kg; whey:
age 25.9 ± 5.9 years, height 1.71 ± 0.10 m, body mass
70.2 ± 11.3 kg; CHO: age 24.9 ± 8.1 years, height
1.70 ± 0.09 m, body mass 70.4 ± 15.3 kg. No significant
differences were observed between treatments at inclusion
in sample characteristics.
Fig. 1 Flow diagram of partici-
pants throughout the course of
the study
Assessed for eligibility (n=54)
Excluded (n=12)
Not meeting inclusion criteria (n=10)
Declined to participate (n=0)
Other reasons (n=2)
Analysed (n= 9)
Excluded from analysis (n=0)
Lost to follow-up (n=5)
Discontinued intervention (n=0)
Allocated to Beef intervention
(n= 14)
Received allocated intervention
(n= 9)
Did not receive allocated
intervention (n=0)
Allocated to Whey intervention
Received allocated intervention
Did not receive allocated
intervention (n=0)
Randomized (n=42)
Allocated to CHO group
(n= 14)
Received allocated intervention
Did not receive allocated
intervention (n=0)
Analysed (n= 9)
Excluded from analysis (n =0)
Analysed (n= 9)
Excluded from analysis (n =0)
Lost to follow-up (n=5)
Discontinued intervention (n=0)
Lost to follow-up (n=5)
Discontinued intervention (n=0)
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270 Eur J Appl Physiol (2017) 117:267–277
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Dietary supplementation
The three products under study were presented as 20 g
sachets of vanilla-flavored powder to be diluted in 250 mL
of cold orange juice at each intake. The diluted drinks were
similar in appearance, texture and taste and were isoener-
getic. The nutritional composition of each product and the
amino acids profile of beef and whey proteins are shown in
Table 1. Products were taken once a day for 8 weeks (56
total doses per participant). On training days (resistance
training or recreational exercise sessions), the supplement
was ingested just after training, whereas on non-training
days, the product was administered in the morning, before
having breakfast.
Dietary (nutrition) monitoring
A research nutritionist collected dietary habits and
explained the proper procedures for recording dietary
intake. Each participant completed a 3-day food diary
report (2 weekdays, and 1 weekend day). The food diary
report was then analyzed using Dietplan 6 software to
determine energy and macronutrient content. Participants
were instructed to maintain their normal diet throughout
the training period. To determine changes and evaluate
differences caused by the supplementation protocol, diet
composition was analyzed again during the last week of the
intervention protocol.
Body composition
Body mass (BM) and height were assessed, on a standard
scale and stadiometer according the methods described by
Ross and Marfel-Jones (1991).
Whole body densitometry was assessed using air dis-
placement via the Bod Pod® (Life Measurements, Concord,
CA, USA) in accordance with the manufacturer’s instruc-
tions as detailed elsewhere (Dempster and Aitkens 1995).
Briefly, the participants were tested wearing only tight fit-
ting clothing (swimsuit or undergarments) and an acrylic
swim cap. Volunteers wore exactly the same clothing for all
testing. Thoracic gas volume was estimated for all partici-
pants using a predictive equation integral to the Bod Pod®
software. The calculated value for body density was used in
the Siri equation (Siri 1961) to estimate the body composi-
tion. A complete body composition measurement was per-
formed twice. If the agreement on percentage of body fat
was within 0.05%, the two tests were averaged. If the two
tests were not within the 0.05% agreement, a third test was
performed and, then, the average of the three completed tri-
als was used for all body composition variables.
Muscular thickness
Right-side vastus medialis muscle thicknesses were meas-
ured in real time using an Diasus diagnostic ultrasound
imaging unit (Dynamic Imaging, Livingston, Scotland
UK) coupled to a 50 mm probe at a frequency of 7.5 MHZ
while participants were lying supine with arms and legs
completely relaxed. The right lower limb was positioned
with the knee extended. The probe was placed perpendicu-
lar to the skin surface and bone tissues at 80% of the dis-
tance between the lateral condyle of the femur and greater
trochanter (Bradley and O’Donnell 2002). The probe was
coated with a water-soluble transmission gel (Aquasonic
100 Ultrasound Transmission gel) to provide acoustic con-
tact without depressing the dermal surface. Thickness was
calculated as the distance between superficial and deep
aponeuroses measured at the ends and middle region of
each 3.8 cm-wide sonograph.
Three images of each muscle were obtained for each
point and the average of the results was calculated. To
favor reproducibility, probe placement was carefully noted
for reproduction during the other test sessions and the
Table 1 Nutritional composition of drinks per intake (20 g of powder
plus 250 mL of orange juice)
EAA essential amino acids, CHO carbohydrates
Nutrient Beef Whey CHO
Energy value (kcal) 184 179 184
Carbohydrates (g) 25 25 45
Lipids (g) 1.54 0.3 0
Proteins (g) 16.4 18 0
Alanine (g) 1.04 1.06
Arginine (g) 1.06 0.38
Aspartic acid (g) 1.50 2.29
Cysteine (g) 0.16 0.48
Glutamic acid (g) 2.58 3.34
Glycine (g) 1.07 0.34
Histidine (g) 0.55 0.31
Isoleucine (g) 0.75 1.00
Leucine (g) 1.32 1.93
Lysine (g) 1.44 1.81
Methionine (g) 0.39 0.44
Phenylalanine (g) 0.65 0.61
Proline (g) 0.81 1.17
Serine (g) 0.65 1.05
Threonine (g) 0.73 1.44
Tryptophan (g) 0.19 0.39
Tyrosine (g) 0.52 5.57
Valine (g) 0.80 0.98
Total EAA (g) 6.82 8.91
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271Eur J Appl Physiol (2017) 117:267–277
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same operator performed all the measurements. To avoid
any swelling in the muscles that could disturb the results,
images were obtained at least 48 h before and after the pro-
gram intervention.
Training, performance evaluation and control of the
intervention compliance
All participants followed the same resistance training rou-
tine, three times per week alternated with their habitual rec-
reational recreationally training (games or team sport ori-
ented activity) for a total of 8 weeks (24 resistance training
workouts). During the 8 weeks of intervention, participants
carried out their workout session late in the afternoon or
early evening. After a warm up, the participants performed
a total of three circuits involving one set of the following
8 resistance exercises: (1) jump-squat (2) bench press, (3)
parallel back squat, (4) upright row, (5) dumbbell alternate
lunges, (6) shoulder press, (7) lateral hurdle jumps, and (8)
abdominal crunch.
Every exercise included 12 maximum repetitions using
the heaviest possible load (except the abdominal crunch
that involved 20 repetitions per sets). A minimum rest was
permitted in between exercises (only the time required to
change from one exercise to the following). Recovery
between circuits was 2–3 min. Resistance training sessions
were completed in about 30 min. All training sessions were
closely monitored to ensure effort, repetitions and inten-
sity established by experienced strength and conditioning
coaches. All participants completed all lifts for each exer-
cise. The total load (kg) summarized all repetitions from
the first six exercises was considered as the indicator of
performance. Although lateral hurdle jumps and abdomi-
nals were performed with no external load, performing
these exercises at the end of every circuit would impact
on general fitness adaptation and the accumulated level of
fatigue over the training session. The first and last workouts
of the intervention period were used as evaluation sessions.
The participants were instructed to refrain from any vigor-
ous activity for 48 h and avoid caffeine ingestion for at least
48 h prior to both assessment sessions. As occurred during
the entire training period, the first and last sessions were
performed at the same time of the day for the same par-
ticipant. After completing the first session, each participant
was given a batch of products, according to randomization.
Tolerance, collected from adverse events and compli-
ance with product intake (determined by an individual
follow up of the participants), was evaluated continuously
during the intervention. Only the participants who com-
pleted all the 24 training sessions were included in the final
Blood indices of health
Blood chemistry samples were taken before and after the
8-week intervention period. Participants arrived at the
physiology laboratory, after a fasting period of 6–8 h, on
two separate occasions (1 day before and 1–2 days after
completing the 8-week intervention period). Finger-prick
capillary whole blood specimens were collected from each
subject, under resting conditions, and analyzed using the
Cholestech LDX Analyzer for fasting total cholesterol,
HDL, LDL cholesterol triglycerides, and glucose, or the
Reflotron Plus Clinical Chemistry Analyzer for CK, cre-
atinine, AST/GOT, ALT/GPT, urea and uric acid. Both
devices were used according to the manufacturer’s instruc-
tions, using test strips (Reflotron Plus Clinical Chemistry
Analyzer) or cassette (Cholestech LDX Analyzer).
Salivary alpha‑defensins HNP1‑3
Saliva collection
Saliva was collected at pre (before and after the first work-
out) and post (before and after the last workout) 8-week
intervention period. At baseline or pre-workout, saliva sam-
ples were collected following the blood samples just a few
minutes before starting the workout. For the post-workout
sample, saliva was collected within 5 min after the exercise
Participants remained seated, performing minimal move-
ment for 10 min (pre-workout) or 5 min (post-workout)
prior to each saliva collection. For all saliva samples, the
mouth was rinsed with water at least 5 min before the col-
lection. The participant was requested to swallow to empty
the mouth before each sample collection. Unstimulated
whole saliva was collected by the spitting method while the
participant remained seated, leaning forward and with the
heads tilted down (Navazesh 1993). Saliva was collected
for 1 min. To avoid circadian variation, saliva samples were
collected in between 2 and 7 pm. The collected saliva was
weighed to obtain precise flow rate (g/min) (Dawidson
et al. 1996). The saliva was stored at 80 °C until further
sample treatment and analysis.
Saliva analysis
Saliva samples were centrifuged (12,000g, 10 min; 4 °C)
and the supernatant diluted 1000× with sample dilution
buffer. Each sample was analyzed in duplicate with ELISA
(Hycult biotech, The Netherlands) following the manu-
factures instructions. The calibration curve consisted of
eight standards, ranging from 0.15 to 10 μg/mL HNP1-3.
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272 Eur J Appl Physiol (2017) 117:267–277
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Absorbance (450 nm) values for the saliva samples were
interpolated from calibration standards with a 4-param-
eter logistic curve (My assays, version 2015). In addition,
the alpha-defensins HNP1-3 secretion rates were deter-
mined by multiplying their concentration by the flow rate
(mL min1).
Statistical analysis
Sensitivity of the final sample size was calculated assum-
ing a model with three groups and four repeated meas-
ures, 0.05 α error probability, and 0.80 power (1 β), to
ensure adequacy of the study. A descriptive analysis was
performed and subsequently the Kolmogorov–Smirnov
and Shapiro–Wilk test were applied to assess normality.
Sample characteristics at baseline were compared between
conditions (beef vs. whey vs. CHO) using one-way anal-
ysis of variance (ANOVA). Change from pre to post in
performance, body composition, muscle thickness, and
blood indices was calculated by subtracting pre- from post-
values. Differences in change between conditions were
assessed using one-way ANOVA. The changes in the con-
centration and secretion of HNP1-3 or the saliva flow rates
were additionally analyzed using three conditions (beef vs.
whey vs. CHO) × four times (pre-workout 1st vs. post-
workout 1st vs. pre-workout 24th vs. post-workout 24th)
repeated measures ANCOVA, using pre-workout 1st as
covariate. Bonferroni-adjusted post hoc analyses were per-
formed when appropriate. Generalized eta squared (
) and
Cohen’s d values were reported to provide an estimate of
standardized effect size (small d = 0.2,
= 0.01; mod-
erate d = 0.5,
= 0.06; and large d = 0.8,
= 0.14).
Significance level was set to p < 0.05. Results are reported
as mean ± SD unless stated otherwise. Data analyses were
performed with Stata 13.1 (StataCorp, College Station, TX,
Fifteen participants (9 male and 6 female) dropped from
the study due to personal reasons, not related with the
intervention protocol. Consequently, 27 participants, 15
males and 12 females (5 (55.5%) and 4 (44.4%) per group,
respectively) successfully completed the study. The sam-
ple was determined to be large enough to detect moderate
group–time interactions (f = 0.26) through a power analy-
sis. The final composition of the three groups was equiva-
lent at baseline (Table 2).
Participants verbally confirmed that they maintained
their diet throughout the trial period. Table 3 shows dietary
monitoring results, presented as the average daily con-
sumption of carbohydrate, protein, fat (g kg1 day1), and
energy (kcal kg1 day1), before and after intervention
Table 2 Treatment groups
description at baseline
All variables are presented as mean (standard deviation); F and p values were calculated using one-way
analysis of variance with 2/24 degrees of freedom
Variable Beef (n = 9) Whey (n = 9) CHO (n = 9) F(2,24) p
Age (years) 25.6 ± 5.3 27.6 ± 5.2 24.4 ± 7.1 0.63 0.539
Height (m) 1.72 ± 0.09 1.73 ± 0.1 1.71 ± 0.08 0.14 0.872
Body mass (kg) 69.9 ± 14.35 70.27 ± 12.52 70.83 ± 10.43 0.01 0.988
Fat (%) 23.47 ± 11.53 18.87 ± 7.95 23.42 ± 11.65 0.57 0.574
Fat-free mass (%) 76.53 ± 11.53 81.13 ± 7.95 76.58 ± 11.65 0.57 0.574
Fat (kg) 18.54 ± 12.66 13.43 ± 6.9 16.89 ± 10.12 0.59 0.560
Fat-free mass (kg) 52.47 ± 7.43 56.85 ± 10.58 53.94 ± 10.23 0.49 0.618
Vastus Medialis thickness (mm) 28.24 ± 4.59 31.93 ± 3.09 30.04 ± 4.67 1.75 0.194
Total loaded (kg) 7403.4 ± 1746.5 7942.5 ± 1675.7 7215.6 ± 1637.8 0.45 0.643
Table 3 Analysis of the participant’s diet composition
* p < 0.05 significant difference from post- to pre-intervention
Treatment Beef Whey CHO
Pre Post Pre Post Pre Post
Proteins (g kg1 day1) 1.45 ± 0.66 1.70 ± 0.70* 1.47 ± 0.75 1.77 ± 0.92* 1.12 ± 0.56 1.12 ± 0.56
CHO (g kg1 day1) 3.39 ± 1.5 3.76 ± 1.59* 3.16 ± 2.23 3.55* (2.22) 2.59 ± 0.98 3.20 ± 1.04*
Fat (g kg1 day1) 1.20 ± 0.55 1.31 ± 0.56* 1.18 ± 0.40 1.18 ± 0.41 0.91 ± 0.12 0.91 ± 0.12
Energy (kcal kg1 day1) 30.99 ± 12.26 33.77 ± 12.41* 29.93 ± 13.50 31.8 ± 13.85* 23.71 ± 7.21 25.83 ± 7.11*
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273Eur J Appl Physiol (2017) 117:267–277
1 3
for the three treatment groups. At baseline, no between-
group differences were observed for the amount of pro-
tein, carbohydrate, fat or energy intake. However, as a
result of the nutritional intervention, all the three groups
increased the intake of carbohydrate, while the beef and
whey groups raised protein consumption but only beef
increased fat intake. All the three treatment groups signifi-
cantly increased the total energy intake, with no difference
between them.
Body composition, muscle thickness, performance
and blood indices of health
Combining resistance training with any of the nutrition
intervention (beef, whey or CHO) did not produce statis-
tically significant differences between the three treatment
conditions in any of the analyzed variables (Table 4).
However, beef showed large effect sizes for body mass
(d = 1.27); total fat-free mass (d = 0.75) vastus medialis
thickness (d = 1.93) and total kg lifted (d = 2.16); mean-
while, the CHO group showed large effect sizes for the
total kg lifted (d = 1.73) and the vastus medialis thickness
(d = 1.04) and so did the whey treatment only for the total
kg lifted (whey d = 0.97).
Salivary alpha‑defensins HNP1‑3
After adjusting for pre-first-workout using ANCOVA, a
significant supplement–time interaction effect for the con-
centration rates (F[6,72] = 2.47, p = 0.031,
= 0.10),
along with statistically significant effect of time
(F[3,72] = 2.69, p = 0.053,
= 0.05), but not differences
between treatment conditions (F[2,23] = 0.65, p = 0.533,
= 0.014), was observed. No significant interaction
(F(6,72) = 1.43, p = 0.215,
= 0.07), treatment condi-
tion (F(2,23) = 0.54, p = 0.591,
= 0.008) or time effect
(F(3,72) = 2.01, p = 0.120,
= 0.05) was determined on
the secretion rates.
Bonferroni-adjusted post hoc contrasts to baseline
revealed no statistically significant differences between
groups at each time point for both the concentration and
secretion rates. However, the beef treatment condition
showed a statistically significant decrease of the base-
line concentration and secretion rates of HNP1-3 from
the values measured before performing the first workout
(1.90 ± 0.83 μg/mL; 2.95 ± 2.83 μg/min, respectively)
of the values determined at post-intervention, before
(0.92 ± 0.63 μg/mL, p = 0.025, d = 1.03; 0.76 ± 0.74 μg/
min, p = 0.049, d = 0.95), and after (0.95 ± 0.60 μg/
mL, p = 0.032, d = 1.00; 0.59 ± 0.52 μg/min, p = 0.027,
d = 1.02) performing the last workout (Fig. 2a, b).
Saliva flow rate
No significant interaction (F[6,72] = 1.49, p = 0.193,
= 0.06) or treatment effect (F[2,24] = 0.47, p = 0.633,
= 0.01) was observed. However, a significant time
effect (F[3,72] = 2.92, p = 0.040,
= 0.06) was deter-
mined. Post hoc analysis revealed a significant intragroup
decrease for the beef treatment condition in saliva flow rate
Table 4 Differences observed
in body composition, muscle
thickness, performance and
blood markers for the three
treatment conditions after the
8-week intervention period
All variables are presented as mean (standard deviation); F and p values were calculated using one-way
analysis of variance with 2/24 degrees of freedom
Variable Beef (n = 9) Whey (n = 9) CHO (n = 9) F(2,24) p
Body weight (kg) 1.28 ± 1 0.26 ± 1.29 0.45 ± 1.59 1.53 0.236
Fat (%) 0.17 ± 1.35 0.41 ± 2.08 0.1 ± 0.44 0.36 0.705
Fat-free mass (%) 0.17 ± 1.35 0.41 ± 2.08 0.1 ± 0.44 0.36 0.705
Fat (kg) 0.47 ± 1.07 0.33 ± 1.62 0.03 ± 0.77 0.99 0.385
Fat-free mass (kg) 0.88 ± 1.18 0.59 ± 0.86 0.42 ± 0.93 0.49 0.618
Vastus medialis thickness (mm) 3.13 ± 1.62 1.57 ± 3.28 1.7 ± 1.63 1.26 0.300
Total loaded (kg) 853.7 ± 395.2 479.1 ± 494.2 763.2 ± 442.3 1.73 0.198
Total cholesterol (mmol/L) 0.09 ± 0.29 0.06 ± 0.46 0.26 ± 0.41 2.19 0.134
HDL cholesterol (mmol/L) 0 ± 0.35 0 ± 0.18 0.11 ± 0.23 0.53 0.593
LDL cholesterol (mmol/L) 0 ± 0.52 0.03 ± 0.5 0.22 ± 0.17 0.95 0.400
Triglycerides (mmol/L) 0.46 ± 0.98 0.17 ± 0.34 0.14 ± 0.72 0.51 0.608
Glucose (mmol/L) 0.48 ± 1.27 0.14 ± 0.85 0.27 ± 0.93 0.84 0.445
Urea (mg/dL) 3.7 ± 9.7 2.71 ± 3.64 2.44 ± 7.58 0.07 0.931
Uric acid (mg/dL) 0.33 ± 0.87 0.18 ± 2.01 0.18 ± 1.06 0.31 0.733
Creatinine (mg) 0.03 ± 0.23 0.15 ± 0.17 0 ± 0.09 2.61 0.094
AST/GOT (U/L) 0.13 ± 4.1 1.52 ± 5.53 3.43 ± 7.57 0.82 0.451
ALT/GPT (U/L) 0.51 ± 2.57 1.99 ± 8.12 2.07 ± 9.25 0.13 0.877
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
274 Eur J Appl Physiol (2017) 117:267–277
1 3
baseline levels from the first to the last training session
at both pre- (1.336 ± 0.752 vs. 0.589 ± 0.398 mL/min,
p = 0.036, d = 0.99) and post-workout (0.928 ± 0.286 vs.
0.470 ± 0.280 mL/min, p = 0.009, d = 0.1.14) sessions.
No significant differences were found between groups at
any time point.
Results suggest that consuming a post-workout carbohy-
drate–protein (beef or whey) beverage during an 8-week
resistance training intervention promotes similar training
and body composition outcomes than ingesting only carbo-
hydrate. The most relevant finding of the present investiga-
tion was the decrease of the baseline levels and secretion
rates of the salivary alpha-defensins HNP1-3 determined
after the 8-week intervention protocol in the beef treatment
condition. A similar non-significant trend was observed for
the whey protein group while no changes were reported for
the participants ingesting only carbohydrates. None of the
treatment conditions (beef, whey or CHO) affected the nor-
mal state of the biochemical blood indices of health or elic-
ited acute changes (pre- to post-workout before and after
intervention) of the HNP1-3.
The increase of diet protein consumption in both beef
and whey treatment group did not produce any nega-
tive effects on the analyzed blood markers of metabolism
or hepatic function. The observed response is expected
because the amount of daily protein intake for the both pro-
tein groups was always within the recommended range of
~1–2 g kg1 (Thomas et al. 2016), Table 3. Indeed, it has
been recently indicated that consuming a high protein diet
(2.6–3.3 g kg1 day1) over a 4-month period has no nega-
tive health-related effect on blood lipids or markers of renal
and hepatic function in healthy resistance trained individu-
als (Antonio et al. 2016).
Data from the present investigation indicate that ingest-
ing a post-workout beverage containing protein with carbo-
hydrate or carbohydrate alone did not influence resistance
training responses during the 8-week training period. Over-
all, the three treatment groups showed similar improve-
ments in body composition, muscle mass and the total kg
lifted over the training intervention. However, the beef
group seems to elicit a slightly superior body mass gain
based on fat-free mass accretion. This appreciation would
be supported by the largest effect size observed for the vas-
tus medialis thickness in beef (d = 1.93) compared to the
other two treatment conditions (whey d = 0.48 and CHO
d = 1.04). Even though previous studies have reported
positive effects of canned, minced or beefsteak beef at
promoting training outcomes in young (Negro et al. 2014)
and elderly individuals (Symons et al. 2009), to the best
of the authors’ knowledge, this is the first study to look at
the effect of a hydrolyzed beef protein powder extract and
compare its effects with those elicited using whey protein
and a non-protein isoenergetic nutrient at supporting resist-
ance training outcomes along with analyses of its impact
on health and immune markers in young athletes. The
total energy provided in the three treatment conditions was
almost similar or the amount of protein provided by beef
and whey was not sufficient to elicit remarkable differences
with respect to the contrast non-protein group. Neverthe-
less, the present results would still support the premise that
daily caloric intake appears to be one of the most relevant
factors affecting training adaptations during middle- to
long-term exercise interventions (McLellan et al. 2014).
In contrast to previous studies (Davison et al. 2009;
Gillum et al. 2015), we did not find acute increases of
Pre Post Pre Post
HNP1-3 secretion rate (µg/min)
Pre PostPre Post
Alpha-defensins HNP1-3 (µg/mL)
Fig. 2 Acute and long-term changes in the concentration (a) and
secretion rates (b) of the alpha-defensins HNP1-3 for the three treat-
ment conditions (mean ± 95% confidence intervals). Statistically sig-
nificant differences were only found from the baseline levels meas-
ured at pre- (before the first workout) to post-intervention, measured
at both before and after the last workout for the beef treatment condi-
tion for both the concentration (p = 0.025 and p = 0.049) and secre-
tion rates (p = 0.032 and p = 0.027), respectively
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275Eur J Appl Physiol (2017) 117:267–277
1 3
HNP1-3 after exercise at both before and after the trained
intervention. Reasons for this discrepancy could be the
nature of the physical exercise. Participants of the present
investigation performed eight different resistance train-
ing exercises while previous studies have used submaxi-
mal cycling (Davison et al. 2009) or running (Gillum et al.
2015) constant intensity protocol. Both aforementioned
studies reported acute increases in the concentration of
HNP1-3 determined immediately after exercise (Davison
et al. 2009; Gillum et al. 2015) or until 1 h compared to
pre-exercise values (Gillum et al. 2015). The post-exercise
rise in the concentration and secretion rate of AMP could
arise from the exercise-induced neutrophilia that occurs in
mucosal secretions potentially due to airway inflammation
or damage to the airway epithelial cells (Muns 1994). In
addition, neutrophilia of the blood can increase HNP1-3 in
saliva (Shiomi et al. 1993). These effects have been asso-
ciated with endurance cyclic exercises such as running or
cycling but not with resistance type exercises. Neutrophils
contain HNP1-3 in addition to other AMP, such as Lacto-
ferrin and Lysozyme (Gleeson 2007). Endurance continu-
ous exercise has been shown to activate neutrophils pos-
sibly causing the release of their contents into the saliva
(Pyne 1994), and this is likely the cause of increased sali-
vary levels of AMP after exercise. Even though participants
of the current investigation were instructed to perform 12
repetitions of each exercise using the maximum possible
amount of load and, consequently, all of them experienced
maximum level of fatigue at the end of every session, no
acute increase in the salivary concentration of HNP1-3 was
determined for both at the beginning and at the end of the
8-week intervention period. Perhaps, the different nature of
the applied training protocol alternating exercises involving
different muscle groups could have influenced the observed
It has been reported that an initial reduction in the con-
centration of some salivary AMP may be an adaptive
response to exercise (West et al. 2010). However, the initial
decrease would not be observed in previously well training
athletes. Participants of the present investigation were rec-
reationally but regular resistance training individuals and
only the participants included in the protein groups (beef
and whey, respectively) showed a significant or a trend
to decrease the levels of HNP1-3. The aforementioned
response would reflect a reduced immune competence with
a concomitant increase in the susceptibility to opportunis-
tic infection that has been reported in well-trained athletes
(West et al. 2010). However, the clinical relevance of the
above-mentioned modification is unknown, since the lev-
els of HNP1-3 measured for the three treatment conditions
were similar to those obtained in previous studies (Davison
et al. 2009; Kunz et al. 2015). In fact, the salivary levels of
AMP including HNP1-3 can vary about 100-fold between
individuals. It is, therefore, difficult to define normal-base-
line reference ranges (Gorr 2009). Nonetheless, when the
individual responses are compared, it is worth noting that
all participants but one in the beef group depicted a con-
sistent decrease in the levels of the HNP1-3 from pre- to
post-intervention, whereas those in the whey and CHO
condition showed different patterns of responses with
three participants in the whey and two in the CHO treat-
ment group showing a reduced concentration of HNP1-3
The HNP1-3 entail a specific group of alpha-defensins
that would increase in response to dental caries and the
respiratory distress syndrome (Kunz et al. 2015). The after
intervention decreased level of HNP1-3 observed in the beef
and whey treatment groups could be related to the reduced
concentration of carbohydrate ingested during the post-
workout period (0.36 ± 0.08 and 0.37 ± 0.06 g kg1 for the
beef and whey groups, respectively, vs. 0.65 ± 0.10 g kg1
for the CHO treatment condition). These results would sup-
port the notion that only carbohydrate ingestion with no
added proteins would probably be the only effective nutri-
tional countermeasure to exercise-induced acute immune
dysfunction (Walsh et al. 2011a). Nonetheless, the effec-
tiveness of ingesting carbohydrate at blunting the post-
exercises immunosuppression has been mainly observed
in acute studies (Walsh et al. 2011a) where the decrease
of different immunological markers including some sali-
vary defensins could be interpreted as a transient immune
dysfunction with a concomitant higher risk of infection or
virus attack (Davison et al. 2009). However, as the drop in
the HNP1-3 level observed in the present study was not
produced acutely but after an 8-week intervention, it can-
not be analyzed as a transient response but as an adaptive
medium- to long-term adaptation similar to that observed
in other salivary markers in well-trained athletes (West
et al. 2010). Considering that HNP1-3 are a marker associ-
ated with exercise stress (Kunz et al. 2015), the lower level
observed after the intervention in the beef group would be
interpreted as a positive adaptive response that allows indi-
viduals to reduce the level of stress determined by a given
exercise protocol. As previously mentioned, neutrophils are
the most abundant white blood cell type and HNP1-3 are
the most abundant antimicrobial peptide secreted by neu-
trophils. Thus, decreased levels of HNP1-3 have also been
proposed as an index of reduced risk factor against virus
and infection (Mehlotra et al. 2016).
The decreased levels of HNP1-3 resulted after the
8-week intervention program, when participants achieved a
better level of performance, which is in line with previous
studies that have reported a lower concentration of salivary
AMP, including HNP1-3 in better-fit athletes (Kunz et al.
2015). Therefore, the reduced HNP1-3 levels observed
after 8 weeks of training could be considered as a normal
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
276 Eur J Appl Physiol (2017) 117:267–277
1 3
adaptive response that might have been hasten by the inges-
tion of the beef protein beverage. Individual differences in
training adaptation can be the reason by which some par-
ticipants allocated in the whey and CHO condition showed
a similar post-intervention reduction in the HNP1-3 levels.
Additionally, the lower average concentration of HNP1-3
was also related to an increased salivary flow rate observed
only for the beef treatment condition. However, differently
from the study of Kunz et al., no differences in perfor-
mance were observed between the three conditions (beef,
whey, and CHO) compared to the present study. The higher
salivary flow rate, observed in the beef group, may act as
a compensatory mechanism to maintain adequate rates of
salivary AMP secretion and may, in fact, be indicative of
greater parasympathetic nervous system activity (resulting
in a large amount of diluted saliva) and vagal tone under
the similar training stimulus (Chicharro et al. 1998; Coote
2010) for this particular group.
It is worthy to note that the large variability in the con-
centration of HNP1-3 observed at rest and in response to
exercise observed in the current study is in accordance
with others (Davison et al. 2009) who have recognized
the variance as a source of limitation for the detection of
intervention-induced changes in mucosal parameters, par-
ticularly in a parallel group design (Jones et al. 2015).
Given the importance of mucosal immune parameters
toward host defense (West et al. 2010), further investigation
of the effects of post-workout feeding strategies on other
salivary AMP (e.g., salivary Lactoferrin and Lysozyme) is
In conclusion, the present investigation suggests that the
ingestion of a carbohydrate–protein (beef or whey) post-
workout beverage may support some possible adaptations
induced by resistance training in a comparable way as the
ingestion of only carbohydrate. Furthermore, the ingestion
of 20 g of protein powder, mainly from hydrolyzed beef
protein, would also promote an early decrease of the aver-
age baseline levels and secretion rates of the salivary alpha-
defensins (HNP1-3) with no negative effect on the blood
indices of health in recreationally trained college athletes.
Acknowledgements Funding was provided by (MEATPROT).
Compliance with ethical standards
Funding MEATPROT and the University of Greenwich provided
joint funding for the completion of this project; however, this does not
affect this original research content and purpose.
Conflict of interest The authors declare that they have no conflicts of
interest relevant to the content of this manuscript.
Open Access This article is distributed under the terms of the Crea-
tive Commons Attribution 4.0 International License (http://crea-, which permits unrestricted use,
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... These compounds are metabolic fuels for both aerobic and anaerobic glycolysis. 4 Thus, the appropriate type, quantity, and time of use of supplements are determinant for the improvement of sports performance and for health promotion. 5 In general, the products used for supplementation should have nutritional function and exert effects on the activation of energy pathways, but anti-inflammatory and immunomodulatory activities are also important. ...
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The population widely uses babassu mesocarp (Attalea speciosa) as food and medicine. This study evaluated the use of babassu mesocarp as a food supplement during resistance training (RT). Male Swiss mice, 60 days old (weight 35-40 g), were divided into four groups (n = 8): control, untreated and untrained; babassu (babassu aqueous extract [BAE]), treated orally with aqueous extract of babassu mesocarp (25 mg/kg), five times a week, for 8 weeks; training (RT), submitted to RT consisting of stair climbing with progressive loads; and resistance training treated with babassu aqueous extract (RTBAE): RT and treatment with BAE. After 8 weeks, we analyzed the biochemistry of serum, the immunological, and histological parameters. The RT group showed maximum strength after the second week. A reduction in body weight, retroperitoneal and interstitial fat deposits, and activated helper T lymphocytes (TCD4+ CD69+) occurred in RT and RTBAE groups. The RTBAE group showed increased levels of aspartate aminotransferase, alanine aminotransferase, and macrophage and helper T lymphocyte count, whereas a reduction occurred in triglyceride levels and the total number of lymphocytes. Supplementation with BAE always reduced cholesterol and the population of activated macrophages but increased activated B lymphocytes and interleukin-6 levels. The combination of supplementation and RT resulted in a decreased production of tumor necrosis factor-α. We propose the use of babassu mesocarp as a food supplement during exercise because of its immunomodulatory effect on lymphocyte and macrophage populations and cytokine production. The additional impact on the control of cholesterol and triglyceride levels suggests its use, particularly for the treatment of dyslipidemias.
Conference Paper
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Protein, yaşam boyu ihtiyaç duyulan temel besin öğesi ve yapı taşıdır. Protein bileşenleri, hücre gelişimi ve fonksiyonu için oldukça önemlidir. Bu nedenle, bireylerin protein tüketimini en az bazal düzeyde karşılayacak kadar sağlaması gereklidir. Tabi bu tüketimlerin istendik ve çeşitli kaynaklardan yapılması daha sağlıklıdır. Sporda, özellikle vücut geliştirme alt dallarında performans sergileyenlerin daha çok yoğunlaştığı protein tüketimi, daha ekonomik görülmesi nedeniyle toz halinde tercih edilmektedir. Bu tip direnç egzersizine dayalı sporlarda temel amaç, antrenmanda oluşan kas hasarlarının giderilmesi ve istenen güç-kuvvetin yakalanabilmesi için gerekli anabolik etkinin sağlanmasıdır. Bu bakımdan, kas kütlesinin artırılmasında oldukça yaygın bir şekilde protein tozu kullanılmaktadır. Bu protein tozları, kullanım amacına göre, antrenman öncesi ya da sonrası, kişinin vücut kütlesine ve yaptığı antrenmanın yoğunluğuna göre değişiklik göstermektedir. Fakat genel sağlık problemlerine de yol açabileceği unutulmamalıdır. İlerleyen zamanlarda, protein sentezi artışına bağlı kalp büyümesi, böbrek hasarı, kanda asidite artışını tolere etmek için kullanılan kemik kalsiyumu ile kemik yapısının zayıflaması, hassasiyetinde artış gibi olumsuz sonuçlar görülebilmektedir. Bu çalışmanın amacı, protein tozu kullanımının egzersiz üzerindeki etkilerini incelemektir. Çalışma, derleme türünde tasarlanmıştır. İlgili literatür taraması yapılarak, sonuçlar tartışılmış ve yorumlanmıştır. Sonuç olarak, uzun süren antrenmanlarda (kuvvet-direnç), sporcuların yaşadığı iştah kaybı nedeniyle, doğal besin alımında isteksizlikler artmaktadır. Bu tip sıkıntılar oluştuğu taktirde protein tozlarına yönelmenin, bunun dışında protein alımını doğal besin tüketimi formlarında tutmanın geleceğe dair daha doğru ve sağlıklı olacağı düşünülmüştür.
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Çok faktörlü bir metabolik bozukluk olan Tip 2 diyabet, dünya çapında artan prevalansı ile küresel salgın halini almıştır. Yüksek kan şekeri, insülin eksikliği ve insülin direnci ile karakterize bir hastalıktır. Genetik ve çevresel faktörlerin etken olduğu Tip 2 diyabet, yaş, obezite, sedanter yaşam tarzı ve yüksek enerji alımı ile ilişkilendirilmektedir. Tip 2 diyabet hastalarında, insülin salınımı yetersiz, glukoz homeostazı bozulmuş durumdadır. Bu diyabet türü, serbest radikallerin artmasına, antioksidan azalmasına ve oksidatif stresin tetiklenmesine neden olmaktadır. Egzersiz, Tip 2 diyabette yaşanan süreçleri kontrol altına alabilen non-farmakolojik yöntem olarak kabul edilir. Farklı şiddetlerde yapılan aerobik egzersizlerin, Tip 2 diyabet göstergelerinde iyileşmelere neden olduğu bilinmektedir. Ayrıca, düzenli yapılan egzersizler, antioksidan kapasiteyi geliştirerek, reaktif oksijen türlerinin neden olduğu oksidatif hasarı azaltabilmektedir. Derleme türünde tasarlanmış bu çalışmada, farklı varyasyonlarda uygulanan interval antrenman yönteminin Tip 2 diyabet hastalığı üzerindeki etkileri incelenmiştir. Sonuç olarak, interval antrenmanların, zaman ekonomisi, fizyolojik fonksiyonların iyileşmesi ve gelişimi bakımından, uzun süreli devamlı egzersizlere nazaran daha etkili olduğu bilinmektedir. Bu çalışmada, belirtilen etkilerin Tip 2 diyabetli hastalar için de geçerli ve önemli olduğu belirlenmiştir. Özellikle yüksek şiddetli interval antrenmanların (HIIT), hastalara bedenen getireceği yük ve kontrendikasyonlar düşünülerek, gözlem altında, doğru bir şekilde planlandığında; etkili, alternatif bir egzersiz protokolü olduğu belirlenmiştir.
Conference Paper
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Tip 2 diyabet (diabetes mellitus/T2DM), küresel bir sağlık tehdidi haline gelmiştir. T2DM gibi metabolik hastalıklar, insidansı hızla artan, uzun süreli zararlı komplikasyonlar taşıyan ve erken ölüme neden olabilen hastalıklardır. Fiziksel egzersiz eksikliği, obezite ve insülin direnci gibi etkenler T2DM’ye yol açabilecek, sürekli risk faktörleri arasındadır. Yeni bir miyokin olarak kabul edilen irisin, egzersiz sırasında iskelet kasları tarafından salınır. Beyaz yağ dokusunun, kahverengileşmesi yönünde uyarım sağlayarak, enerji tüketimini artırır. Diğer yandan da yağ yakımını destekler. Bu özellikleri nedeniyle, son zamanlarda diyabet ve irisin ilişkisi oldukça merak uyandırmaktadır. Bu çalışmanın amacı, tip 2 diyabet ve irisin arasında ilişki olup olmadığının incelenmesidir. Çalışmada, egzersiz sırasında iskelet kasındaki etkinliği ile diyabetli hastalar için tedavide yardımcı faktör olabileceği düşünülen irisin araştırılmıştır. Çalışma, derleme türünde yapılmış olup, PubMed gibi bilimsel araştırma ve dergi ağlarından, uluslararası, etki faktörü yüksek kaynaklar aracılığıyla alanyazın desteği sağlanmıştır. Sonuç olarak, irisin (dolaşımda) ve insülin direnci arasında negatif yönlü bir ilişki olduğu, yani irisin salınımı arttıkça direncin azaldığı belirlenmiştir. Artmış irisin, kan şekerini azaltmakta, hücre (pankreas) ölümünü engellemekte, karaciğer hücrelerinde ve iskelet kası hücrelerinde glukoz metabolizmasını iyileştirmektedir.
Conference Paper
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Diyabet (Tip 2 Diabetes Mellitus), insülin direnci veya insülin salınımında eksiklik olarak tanımlanan metabolik hastalıktır. Toplumda, diyabetli hastaların büyük çoğunluğu Tip 2 diyabet (Tip 2 DM) türünde seyretmektedir. Genetik ve çevresel faktörler Tip 2 DM’nin etiyolojisini oluşturmaktadır. Aynı zamanda, yaş, obezite, süreğen olarak gereğinden fazla enerji alımı ve yaşam tarzı ile ilişkilendirilir. Tip 2 DM, toplumda sık görülen ve kronik bir hastalık olarak kabul edilir. Hastalığın hızla atarak yayılması, inaktif bir yaşam tarzının benimsenmesi temeline dayanmaktadır. Fiziksel aktivitedeki düşüşler, hipokinetik (hareketlerin aşırı yavaşlaması) ve sinirsel hareket bozukluğuna dayalı hastalıkları da beraberinde getirmektedir. Bu çalışmanın amacı, egzersizin diyabetli hastalar üzerindeki etkilerini araştırmaktır. Çalışmada, diyabet üzerinde iyileştirici etkilerinin olduğu düşünülen egzersizin yarattığı sonuçlar incelenmiştir. İnsülin direnci nedeniyle, hücre içine giremeyen ya da sınırlı girebilen glukoz için egzersiz sayesinde yeni bir yol açılabileceği düşünülmektedir. Çalışma, derleme türünde tasarlanmış, ilgili literatür taraması özetlenerek sunulmuştur. Sonuç olarak, hekim kontrolünde, standart tedavilerin yanı sıra düzenli egzersizin, hastaların yaşam kalitelerini artıracağı belirlenmiştir. Kişilerin bireysel durumları göz önüne alınarak, doğru planlanmış, şiddet, sıklık ve süreleri iyi organize edilmiş egzersizlerle, hem yağ yakımı artırılabilir hem de insülin sekresyonu onarılabilir.
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Objectives This systematic review, meta-analysis, and meta-regression aimed to determine if increasing daily protein ingestion contributes to gaining lean mass (LM), muscle strength, and physical/functional test performance in healthy persons. Methods The present review was registered on PROSPERO - CRD42020159001. A systematic search in Medline, Embase, CINAHL, and Web of Sciences databases was undertaken. Randomized controlled trials (RCT) including healthy and non-obese adult participants increasing daily protein intake were selected. Subgroup analysis, splitting the studies by participation in resistance exercise training (RE), age (< 65 or ≥ 65 y), and daily protein ingestion were also performed. Results 74 RCT fit our inclusion criteria. The age range of the participants was 19 to 85 y, and study protocols in the trials lasted from 6 to 108 wks (76% of the studies between 8 and 12 wks). In ∼80% of the studies, baseline protein ingestion was at least 1.2 g of protein/kg/d. Increasing daily protein ingestion may lead to small gains in LM in subjects enrolled in RE (SMD [standardized mean difference] = 0.22, CI95% [95% confidence interval] 0.14:0.30, P < 0.01, 62 studies, moderate level of evidence). Also, ≥ 65 y subjects ingesting 1.2–1.59 g of protein/kg/d and younger subjects (< 65 y) increasing their ingestion to ≥ 1.6 g of protein/kg/d during RE showed a higher LM gain. Lower-body strength gain was slightly higher at ≥ 1.6 g of protein/kg/d during RE (SMD = 0.40, CI95% 0.09:0.35, P < 0.01, 19 studies, low level of evidence). Bench press strength was slightly increased by ingesting more protein in < 65 y subjects during RE (SMD = 0.18, CI95% 0.03:0.33, P = 0.01, 32 studies, low level of evidence). Effects on handgrip strength are unclear and only marginal for performance in physical function tests. Conclusions The number of studies increasing daily protein ingestion alone was too low (n = 6) to conduct a meta-analysis. The current evidence shows that increasing protein ingestion by consuming supplements or food, resulted in small additional gain in LM, and lower body muscle strength in healthy adults enrolled in RE. Effects on bench press strength and performance in physical function tests are minimal. The effect on handgrip strength was unclear. Funding Sources This research received a grant from the International Life Science Institute (Europe) and CNPq.
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Abstract We performed a systematic review, meta‐analysis, and meta‐regression to determine if increasing daily protein ingestion contributes to gaining lean body mass (LBM), muscle strength, and physical/functional test performance in healthy subjects. A protocol for the present study was registered (PROSPERO, CRD42020159001), and a systematic search of Medline, Embase, CINAHL, and Web of Sciences databases was undertaken. Only randomized controlled trials (RCT) where participants increased their daily protein intake and were healthy and non‐obese adults were included. Research questions focused on the main effects on the outcomes of interest and subgroup analysis, splitting the studies by participation in a resistance exercise (RE), age (
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This pre print describes the development of a protocol to image and measure vastus lateralis muscle morphology using B mode ultrasound.
The quality of the existing evidence on the effects of protein hydrolysate supplementation on fat-free mass (FFM) and upper and lower body strength under resistance exercise intervention has not been evaluated. We conducted a structured literature search in PubMed, Web of Science, Cochrane Library, and Scopus database. A random effect model was used with continuous data of FFM and upper and lower body strength for healthy participants over 18 years old who received resistance training for ≥4 weeks and took protein hydrolysate or equivalent control supplements. Sensitivity and subgroup analyses were also conducted. Data from 330 participants in eight studies showed that supplemental protein hydrolysate had a positive effect on the FFM (n = 13, SMD = 0.36, 95% confidence interval (CI): 0.16–0.56, P = 0.000) and lower (n = 7, SMD = 0.43, 95% CI: 0.16–0.69, P = 0.001) and upper (n = 5, SMD = 0.17, 95% CI: −0.06–0.41, P = 0.145) body strength of resistance-trained individuals compared with placebo, showing an increase in physical fitness and muscle strength. However, the current evidence is insufficient to establish ingestion recommendations.
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Background: Resistance exercise leads to net muscle protein accretion through a synergistic interaction of exercise and feeding. Proteins from different sources may differ in their ability to support muscle protein accretion because of different patterns of postprandial hyperaminoacidemia. Objective: We examined the effect of consuming isonitrogenous, isoenergetic, and macronutrient-matched soy or milk beverages (18 g protein, 750 kJ) on protein kinetics and net muscle protein balance after resistance exercise in healthy young men. Our hypothesis was that soy ingestion would result in larger but transient hyperaminoacidemia compared with milk and that milk would promote a greater net balance because of lower but prolonged hyperaminoacidemia. Design: Arterial-venous amino acid balance and muscle fractional synthesis rates were measured in young men who consumed fluid milk or a soy-protein beverage in a crossover design after a bout of resistance exercise. Results: Ingestion of both soy and milk resulted in a positive net protein balance. Analysis of area under the net balance curves indicated an overall greater net balance after milk ingestion (P < 0.05). The fractional synthesis rate in muscle was also greater after milk consumption (0.10 ± 0.01%/h) than after soy consumption (0.07 ± 0.01%/h; P = 0.05). Conclusions: Milk-based proteins promote muscle protein accretion to a greater extent than do soy-based proteins when consumed after resistance exercise. The consumption of either milk or soy protein with resistance training promotes muscle mass maintenance and gains, but chronic consumption of milk proteins after resistance exercise likely supports a more rapid lean mass accrual.
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Both α- and β-defensins have anti-human immunodeficiency virus activity. These defensins achieve human immunodeficiency virus inhibition through a variety of mechanisms, including direct binding with virions, binding to and modulation of host cell-surface receptors with disruption of intracellular signaling, and functioning as chemokines or cytokines to augment and alter adaptive immune responses. Polymorphisms in the defensin genes have been associated with susceptibility to human immunodeficiency virus infection and disease progression. However, the roles that these defensins and their genetic polymorphisms have in influencing human immunodeficiency virus/acquired immunodeficiency syndrome outcomes are not straightforward and, at times, appear contradictory. Differences in populations, study designs, and techniques for genotyping defensin gene polymorphisms may have contributed to this lack of clarity. In addition, a comprehensive approach, where both subfamilies of defensins and their all-inclusive genetic polymorphism profiles are analyzed, is lacking. Such an approach may reveal whether the human immunodeficiency virus inhibitory activities of α- and β-defensins are based on parallel or divergent mechanisms and may provide further insights into how the genetic predisposition for susceptibility or resistance to human immunodeficiency virus/acquired immunodeficiency syndrome is orchestrated between these molecules.
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It is the position of the Academy of Nutrition and Dietetics (Academy), Dietitians of Canada (DC), and the American College of Sports Medicine (ACSM) that the performance of, and recovery from, sporting activities are enhanced by well-chosen nutrition strategies. These organizations provide guidelines for the appropriate type, amount, and timing of intake of food, fluids, and supplements to promote optimal health and performance across different scenarios of training and competitive sport. This position paper was prepared for members of the Academy, DC, and ACSM, other professional associations, government agencies, industry, and the public. It outlines the Academy’s, DC’s, and ACSM’s stance on nutrition factors that have been determined to influence athletic performance and emerging trends in the field of sports nutrition. Athletes should be referred to a registered dietitian nutritionist for a personalized nutrition plan. In the United States and in Canada, the Certified Specialist in Sports Dietetics is a registered dietitian nutritionist and a credentialed sports nutrition expert.
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Background: Eight weeks of a high protein diet (>3 g/kg/day) coupled with a periodized heavy resistance training program has been shown to positively affect body composition with no deleterious effects on health. Using a randomized, crossover design, resistance-trained male subjects underwent a 16-week intervention (i.e., two 8-week periods) in which they consumed either their normal (i.e., habitual) or a higher protein diet (>3 g/kg/day). Thus, the purpose of this study was to ascertain if significantly increasing protein intake would affect clinical markers of health (i.e., lipids, kidney function, etc.) as well as performance and body composition in young males with extensive resistance training experience. Methods: Twelve healthy resistance-trained men volunteered for this study (mean ± SD: age 25.9 ± 3.7 years; height 178.0 ± 8.5 cm; years of resistance training experience 7.6 ± 3.6) with 11 subjects completing most of the assessments. In a randomized crossover trial, subjects were tested at baseline and after two 8-week treatment periods (i.e., habitual [normal] diet and high protein diet) for body composition, measures of health (i.e., blood lipids, comprehensive metabolic panel) and performance. Each subject maintained a food diary for the 16-week treatment period (i.e., 8 weeks on their normal or habitual diet and 8 weeks on a high protein diet). Each subject provided a food diary of two weekdays and one weekend day per week. In addition, subjects kept a diary of their training regimen that was used to calculate total work performed. Results: During the normal and high protein phase of the treatment period, subjects consumed 2.6 ± 0.8 and 3.3 ± 0.8 g/kg/day of dietary protein, respectively. The mean protein intake over the 4-month period was 2.9 ± 0.9 g/kg/day. The high protein group consumed significantly more calories and protein (p < 0.05) than the normal protein group. There were no differences in dietary intake between the groups for any other measure. Moreover, there were no significant changes in body composition or markers of health in either group. There were no side effects (i.e., blood lipids, glucose, renal, kidney function etc.) regarding high protein consumption. Conclusion: In resistance-trained young men who do not significantly alter their training regimen, consuming a high protein diet (2.6 to 3.3 g/kg/day) over a 4-month period has no effect on blood lipids or markers of renal and hepatic function. Nor were there any changes in performance or body composition. This is the first crossover trial using resistance-trained subjects in which the elevation of protein intake to over four times the recommended dietary allowance has shown no harmful effects.
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The goal of this critical review is to comprehensively assess the evidence for the molecular, physiologic, and phenotypic skeletal muscle responses to resistance exercise (RE) combined with the nutritional intervention of protein and/or amino acid (AA) ingestion in young adults. We gathered the literature regarding the translational response in human skeletal muscle to acute exposure to RE and protein/AA supplements and the literature describing the phenotypic skeletal muscle adaptation to RE and nutritional interventions. Supplementation of protein/AAs with RE exhibited clear protein dose-dependent effects on translational regulation (protein synthesis) through mammalian target of rapamycin complex 1 (mTORC1) signaling, which was most apparent through increases in p70 ribosomal protein S6 kinase 1 (S6K1) phosphorylation, compared with postexercise recovery in the fasted or carbohydrate-fed state. These acute findings were critically tested via long-term exposure to RE training (RET) and protein/AA supplementation, and it was determined that a diminishing protein/AA supplement effect occurs over a prolonged exposure stimulus after exercise training. Furthermore, we found that protein/AA supplements, combined with RET, produced a positive, albeit minor, effect on the promotion of lean mass growth (when assessed in >20 participants/treatment); a negligible effect on muscle mass; and a negligible to no additional effect on strength. A potential concern we discovered was that the majority of the exercise training studies were underpowered in their ability to discern effects of protein/AA supplementation. Regardless, even when using optimal methodology and large sample sizes, it is clear that the effect size for protein/AA supplementation is low and likely limited to a subset of individuals because the individual variability is high. With regard to nutritional intakes, total protein intake per day, rather than protein timing or quality, appears to be more of a factor on this effect during long-term exercise interventions. There were no differences in strength or mass/muscle mass on RET outcomes between protein types when a leucine threshold (>2 g/dose) was reached. Future research with larger sample sizes and more homogeneity in design is necessary to understand the underlying adaptations and to better evaluate the individual variability in the muscle-adaptive response to protein/AA supplementation during RET.
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Skeletal muscle mass is regulated by a balance between muscle protein synthesis (MPS) and muscle protein breakdown (MPB). In healthy humans, MPS is more sensitive (varying 4-5 times more than MPB) to changes in protein feeding and loading rendering it the primary locus determining gains in muscle mass. Performing resistance exercise (RE) followed by the consumption of protein results in an augmentation of MPS and, over time, can lead to muscle hypertrophy. The magnitude of the RE-induced increase in MPS is dictated by a variety of factors including: the dose of protein, source of protein, and possibly the distribution and timing of post-exercise protein ingestion. In addition, RE variables such as frequency of sessions, time under tension, volume, and training status play roles in regulating MPS. This review provides a brief overview of our current understanding of how RE and protein ingestion can influence gains in skeletal muscle mass in young, healthy individuals. It is the goal of this review to provide nutritional recommendations for optimal skeletal muscle adaptation. Specifically, we will focus on how the manipulation of protein intake during the recovery period following RE augments the adaptive response.
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We investigated the effects of ingesting a multi-ingredient (53g carbohydrate, 14.5g whey protein , 5g glutamine, 1.5g L-carnitine-L-tartrate) supplement, carbohydrate only, or placebo on intermittent performance, perception of fatigue, immunity, and functional and metabolic markers of recovery. Sixteen amateur soccer players ingested their respective treatments before, during and after performing a 90-min intermittent repeated sprint test. Primary outcomes included time for a 90-min intermittent repeated sprint test (IRS) followed by eleven 15 m sprints. Measurements included creatine kinase, myoglobin, interleukine-6, Neutrophil; Lymphocytes and Monocyte before (pre), immediately after (post), 1h and 24h after exercise testing period. Overall , time for the IRS and 15 m sprints was not different between treatments. However, the perception of fatigue was attenuated (P<0.001) for the multi-ingredient (15.9±1.4) vs. placebo (17.8±1.4) but not for the carbohydrate (17.0±1.9) condition. Several changes in immune/in-flammatory indices were noted as creatine kinase peaked at 24h while Interleukin-6 and myo-globin increased both immediately after and at 1h compared with baseline (P<0.05) for all three conditions. However, Myoglobin (P<0.05) was lower 1h post-exercise for the multi-ingredient (241.8±142.6 ngÁml
Bovine colostrum (COL) has been advocated as a nutritional countermeasure to exercise-induced immune dysfunction. The aims of this study were to identify the effects of 4 weeks of COL supplementation on neutrophil responses and mucosal immunity following prolonged exercise. In a randomized double-blind, parallel group design, participants [age 28 ± 8 years; body mass 79 ± 7 kg; height 182 ± 6 cm; maximal oxygen uptake ( V ˙ O 2 m a x ) 55 ± 9 mL/kg/min] were assigned to 20 g per day of COL (n = 10) or an isoenergetic/isomacronutrient placebo (PLA; n = 10) for 4 weeks. Venous blood and unstimulated saliva samples were obtained before and after 2.5 h of cycling at 15% Δ (∼55-60% V ˙ O 2 m a x ). A significantly greater formyl-methionyl-leucyl phenylalanine-stimulated oxidative burst was observed in the COL group compared with PLA group (P < 0.05) and a trend toward a time × group interaction (P = 0.06). However, there was no effect of COL on leukocyte trafficking, phorbol-12-myristate-13-acetate-stimulated oxidative burst, bacterial-stimulated neutrophil degranulation, salivary secretory IgA, lactoferrin or lysozyme (P > 0.05). These findings provide further evidence of the beneficial effects of COL on receptor-mediated stimulation of neutrophil oxidative burst in a model of exercise-induced immune dysfunction. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Sleep deficiencies may play a role in depressing immune parameters. Little is known about the impact of exercise after sleep deprivation on mucosal immunity. The purpose was to quantify salivary antimicrobial proteins (AMPs) in response to sleep loss before and after exercise. 4 males and 4 females, (age: 22.8+/-2; VO2pk: 49.1+/-7.1 mL/kg/min) completed 2 exercise trials consisting of 45 min of running at 75% VO2pk after a normal night of sleep (CON) and after a night without sleep (WS). Exercise trials were separated by 10+/-3 days. Saliva was collected before, immediately after, and 1 hr after exercise. LL-37, HNP1-3, Lactoferrin (Lac) and Lysozyme (Lys) were measured. Sleep loss did not affect the concentration or secretion rate of AMPs before or in response to exercise. However, exercise increased the concentration from pre to post exercise of LL-37 (pre: 15.5+/-8.7; post: 22.3+/-16.2 ng/mL), HNP1-3 (pre: 2.2+/-2.3; post: 3.3+/-2.5 [micro]g/mL), Lac (pre: 5234+/-4202; post: 12283+/-10995 ng/mL), and Lys (pre: 5831+/-4465; post: 12542+/-10755 ng/mL), p<0.05. The secretion rates were higher immediately post and 1 hr post exercise compared to pre exercise for LL-37 (pre: 3.1+/-2.1; post: 5.1+/-3.7; +1: 6.9+/-8.4 ng/min), HNP1-3 (pre: 0.38+/-0.38; post: 0.80+/-0.75; +1: 0.84+/-0.67 [micro]g/min), Lac (pre: 1096+/-829; post: 2948+/-2923; +1: 2464+/-3785 ng/min), and Lys (pre: 1534+/-1790; post: 3042+/-2773; +1: 1916+/-1682 ng/min), p<0.05. These data suggests that the major constituents of the mucosal immune system are unaffected by acute sleep loss and by exercise following acute sleep loss. Exercise increased the concentration and secretion rate of each AMP suggesting enhanced immunity and control of inflammation, despite limited sleep.
Purpose: Salivary antimicrobial proteins (sAMPs) protect the upper respiratory tract (URTI) from invading microorganisms and have been linked with URTI infection risk in athletes. While high training volume is associated with increased URTI risk, it is not known if fitness affects the sAMP response to acute exercise. This study compared the sAMP responses to various exercising workloads of highly fit experienced cyclists with those who were less fit. Methods: Seventeen experienced cyclists (nine highly fit; eight less fit) completed three 30-min exercise trials at workloads corresponding to -5, +5 and +15 % of the individual blood lactate threshold. Saliva samples were collected pre- and post-exercise to determine the concentration and secretion of α-amylase, human neutrophil proteins 1-3 (HNP1-3) lactoferrin, LL-37, lysozyme, and salivary SIgA. Results: The concentration and/or secretion of all sAMPs increased post-exercise, but only α-amylase was sensitive to exercise workload. Highly fit cyclists had lower baseline concentrations of α-amylase, HNP1-3, and lactoferrin, although secretion rates did not differ between the groups. Highly fit cyclists did, however, exhibit greater post-exercise increases in the concentration and/or secretion of a majority of measured sAMPs (percentage difference between highly fit and less fit in parentheses), including α-amylase concentration (+107 %) and secretion (+148 %), HNP1-3 concentration (+97 %) and secretion (+158 %), salivary SIgA concentration (+181 %), lactoferrin secretion (+209 %) and LL-37 secretion (+138 %). Conclusion: We show for the first time that fitness level is a major determinant of exercise-induced changes in sAMPs. This might be due to training-induced alterations in parasympathetic and sympathetic nervous system activation.