Category Archives: Publications

Effects of high-intensity interval training on central haemodynamics and skeletal muscle oxygenation during exercise in patients with chronic heart failure

Spee, Ruud F; Niemeijer, Victor M; Wijn,
Pieter F; Doevendans, Pieter A; Kemps, Hareld M.

European Journal of Preventive Cardiology, December 2016, Vol. 23 Issue: Number 18
p1943-1952, 10p

Abstract: Background
High-intensity interval training
(HIT) improves exercise capacity in patients with chronic heart failure
(CHF). Moreover, HIT was associated with improved resting cardiac
function. However, the extent to which these improvements actually
contribute to training-induced changes in exercise capacity remains to
be elucidated. Therefore, we evaluated the effects of HIT on exercising
central haemodynamics and skeletal muscle oxygenation.Methods
Twenty-six CHF patients were randomised to a 12-week 4 × 4 minute HIT
program at 85–95% of peak VO2or usual care. Patients performed maximal
and submaximal cardiopulmonary exercise testing with simultaneous
assessment of cardiac output and skeletal muscle oxygenation by near
infrared spectroscopy, using the amplitude of the tissue saturation
index (TSIamp).

Results  Peak workload increased by 11% after HIT
(pbetween group = 0.01) with a non-significant increase in peak
VO2(+7%, pbetween group = 0.19). Cardiac reserve increased by 37% after
HIT (p within group = 0.03, pbetween group = 0.08); this increase was
not related to improvements in peak workload. Oxygen uptake recovery
kinetics after submaximal exercise were accelerated by 20% (pbetween
group = 0.02); this improvement was related to a decrease in TSIamp
(r= 0.71, p= 0.03), but not to changes in cardiac output
kinetics.

Conclusion  HIT induced improvements in maximal exercise
capacity and exercising haemodynamics at peak exercise. Improvements in
recovery after submaximal exercise were associated with attenuated
skeletal muscle deoxygenation during submaximal exercise, but not with
changes in cardiac output kinetics, suggesting that the effect of HIT
on submaximal exercise capacity is mediated by improved microvascular
oxygen delivery-to-utilisation matching.; (AN 40419387)

Systematic review: pre‐ and post‐operative prognostic value of cardiopulmonary exercise testing in liver transplant candidates

Ney,  M.; Haykowsky, M. J.; Vandermeer, B.; Shah, A.; Ow, M.; Tandon, P..
Alimentary Pharmacology & Therapeutics, October 2016, Vol. 44 Issue:
Number 8 p796-806, 11p;

Abstract: Cardiopulmonary exercise testing
(CPET) is the gold standard for the objective assessment of functional
status. In many conditions, CPET outperforms the traditional variables
in predicting mortality. In patients with cirrhosis listed for liver
transplantation, our primary aim was to determine the prognostic value
of CPET for pre‐and post‐transplant mortality and, in particular,
whether CPET remained predictive after adjustment for liver disease
severity. A systematic literature review was conducted in databases
Medline, Scopus, Embase and PubMed. Where possible, data were pooled
for meta‐analyses using a DerSimonian and Laird random effects model. A
total of seven studies were retrieved, including 1107 patients with a
mean MELD of 14.2 (standard deviation 1.6) and peak baseline VO2of 17.4
mL/kg/min. In all of the studies in which multivariable analysis was
performed, CPET variables were independent predictors of pre‐transplant
mortality (three studies) and post‐transplant mortality (four studies).
In the three studies where we could aggregate post‐transplant mortality
data, post‐transplant mortality was predicted by AT with a mean
difference of 2.0 (95% confidence interval, CI: 0.42–3.59; Z= 2.48, P=
0.01) between survivors and nonsurvivors. The peak VO2was not
significant (0.77 95% CI: −1.36 to 2.90; Z= 0.71, P= 0.48). Patient’s
listed for liver transplant have significant functional limitations,
with a weighted mean VO2 below the threshold level required for
independent living. Although heterogeneity in study designs with
respect to timing, CPET variables, and cut‐off values precluded the
determination of CPET mortality thresholds, the studies support CPET as
an objective and independent predictor of pre‐ and post‐transplant
mortality.

Potential Effects on Cardiorespiratory and Metabolic Status After a Concurrent Strength and Endurance Training Program in Diabetes Patients — a Randomized Controlled TrialPotential Effects on Cardiorespiratory and Metabolic Status After a Concurrent Strength and Endurance Training Program in Diabetes Patients — a Randomized Controlled Trial

Bassi, Daniela; Mendes, Renata; Arakelian, Vivian; Caruso, Flávia; Cabiddu, Ramona; Júnior, José;
Arena, Ross; Borghi-Silva, Audrey.

Sports Medicine – Open, December 2016, Vol. 2 Issue: Number 1 p1-13, 13p;

Abstract: Concurrent aerobic and resistance training (CART) programs have been widely recommended as
an important strategy to improve physiologic and functional performance
in patients with chronic diseases. However, the impact of a
personalized CART program in patients with type 2 diabetes (T2D)
requires investigation. Therefore, the primary aim of the current study
is to investigate the impact of CART programs on metabolic profile,
glycemic control, and exercise capacity in patients with diabetes.
We evaluated 41 subjects with T2D (15 females and 19
males, 50.8 ± 7 years); subjects were randomized into two groups;
sedentary (SG) and CART (CART-G). CART was performed over 1.10-h
sessions (30-min aerobic and 30-min resistance exercises) three
times/week for 12 weeks. Body composition, biochemical analyses,
peripheral muscular strength, and cardiopulmonary exercise testing were
primary measurements.                   The glycated hemoglobin HbA1c
(65.4 ± 17.9 to 55.9 ± 12.7 mmol/mol), cholesterol (198.38.1 ± 50.3 to
186.8 ± 35.1 mg/dl), and homeostasis model assessment insulin
resistance (HOMA-IR) (6.4 ± 6.8 to 5.0 ± 1.4) decreased in the CART-G
compared to the SG. Although body weight did not significantly change
after training, skinfold measurement indicated decreased body fat in
the CART-G only. CART significantly enhanced muscle strength compared
to the SG (p< 0.05). CART was also associated with significant increase
in peak oxygen uptake and maximal workload compared to the SG
(p< 0.05).                   These data support CART as an important
strategy in the treatment of patients with T2D, producing both
physiologic and functional improvements.

FACTORS AFFECTING THE COMPONENTS OF THE ALVEOLAR C02 OUTPUT-02 UPTAKE RELATIONSHIP DURING INCREMENTAL EXERCISE IN MAN [1991!!]

CHRISTOPHER B. COOPER, WILLIAM L. BEAVER, DAN M. COOPER
AND KARLMAN WASSERMAN
Experimental Physiology (1992), 77, 51-64

The V VO (alveolar CO2 output-alveolar 02 uptake) relationship ( V-slope) during increasing
work rate (r-amp) cycle ergometer exercise has two approximately linear components: a lower
component slope (S,) with a value of about 0-95 and a steeper, upper component (S2). We
examined the effect of muscle glycogen depletion (protocol 1) and the rate of increase in work
rate (ramp rate) without muscle glycogen depletion (protocol 2) on S1 and S2. In protocol 1,
ten healthy men with a mean age of 31 4 years (S.D. 6-2) were studied on each of 3 days (days
I and 3 were control days). They performed a ramp exercise test to maximum tolerance and
steady-state tests at rest, during unloaded pedalling and at two constant work rates below their
anaerobic threshold (AT). To deplete muscle glycogen before the test on day 2, the subjects
performed 2 h of very heavy cycle exercise on the preceding day and fasted overnight. Si was
reduced on day 2 (0 79 compared with 0 95, P < 0 001), as was the VC0 -VO slope derived
from steady-state measurements (0 81 compared with 0 99, P < 0 001), but AT and the slope
difference (S2 -S5) were unchanged. In protocol 2, seven healthy men with a mean age of 20 6
years (S.D. 2-4) performed ramp tests at three different rates of increasing work rate (1 5, 30 and
60 W min’), each ramp rate being performed twice in random sequence. The ramp rate did not
affect Si but S2 was steeper with the faster rates of work rate increase (127, 143 and 163,
respectively, P < 0 01). Our findings support the concept that the lower component of the Vslope
plot (below AT) represents muscle substrate respiratory quotient (RQ) while the
difference between Si and S2 reflects ‘excess CO2’ derived from bicarbonate buffering of lactic
acid.

FACTORS AFFECTING THE COMPONENTS OF THE ALVEOLAR C02 OUTPUT-02 UPTAKE RELATIONSHIP DURING INCREMENTAL EXERCISE IN MAN [1991!!]

CHRISTOPHER B. COOPER, WILLIAM L. BEAVER, DAN M. COOPER
AND KARLMAN WASSERMAN

The V VO (alveolar CO2 output-alveolar 02 uptake) relationship ( V-slope) during increasing
work rate (r-amp) cycle ergometer exercise has two approximately linear components: a lower
component slope (S,) with a value of about 0-95 and a steeper, upper component (S2). We
examined the effect of muscle glycogen depletion (protocol 1) and the rate of increase in work
rate (ramp rate) without muscle glycogen depletion (protocol 2) on S1 and S2. In protocol 1,
ten healthy men with a mean age of 31 4 years (S.D. 6-2) were studied on each of 3 days (days
I and 3 were control days). They performed a ramp exercise test to maximum tolerance and
steady-state tests at rest, during unloaded pedalling and at two constant work rates below their
anaerobic threshold (AT). To deplete muscle glycogen before the test on day 2, the subjects
performed 2 h of very heavy cycle exercise on the preceding day and fasted overnight. Si was
reduced on day 2 (0 79 compared with 0 95, P < 0 001), as was the VC0 -VO slope derived
from steady-state measurements (0 81 compared with 0 99, P < 0 001), but AT and the slope
difference (S2 -S5) were unchanged. In protocol 2, seven healthy men with a mean age of 20 6
years (S.D. 2-4) performed ramp tests at three different rates of increasing work rate (1 5, 30 and
60 W min’), each ramp rate being performed twice in random sequence. The ramp rate did not
affect Si but S2 was steeper with the faster rates of work rate increase (127, 143 and 163,
respectively, P < 0 01). Our findings support the concept that the lower component of the Vslope
plot (below AT) represents muscle substrate respiratory quotient (RQ) while the
difference between Si and S2 reflects ‘excess CO2’ derived from bicarbonate buffering of lactic acid.

Influence of increased metabolic rate on [ 13C] bicarbonate washout kinetics

BARSTOW, THOMAS J., DAN M. COOPER, ERIC M. SOBEL,
ELLIOT M. LANDAW, AND SAM EPSTEIN.

Am. J. Phvsiol. 259 (Regulatory Integrative Comp. Physiol. 28): Rl63-
Rl?l, 1990.-

The effect of changes in metabolic rate on the
dynamics of CO, exchange among its various compartments in
the human body is not well understood. We examined COz
dynamics in six healthy male subjects using an intravenous
bolus of [ “‘Clbicarbonate. Subjects were studied while resting,
during light exercise [50% of the lactate threshold (LT), 3-4
times resting 0, uptake (VOW)], and during moderate exercise
(95% of the LT, 6 times resting VO,). The sum of three
exponential terms well described the washout of 1’3C02 in exhaled
breath both at rest and during each exercise level despite
substantial increases in metabolic rate accompanying the exercise
studies. Average recovery of “‘C label rose from 67%
during rest to 80% during light and moderate exercise (P <
0.01). The estimate of CO, elimination (ho2) calculated from
the washout parameters and corrected for recovery was in very
good agreement with the VCO~ directly measured simultaneously
breath by breath (r = 0.993, SE for VCO~ = 0.079 l/min).
By use of a three-compartment mammillary model, the quantity
of CO, in the central pool (Q1) doubled from rest to light
exercise (233 & 60 to 479 t 76 mmol, P < 0.01) but did not
change further with moderate exercise (458 & 74 mmol). Rate
constants for exchange between pools and for irreversible loss
from the system tended to increase with metabolic rate, but
there was large variation in the responses. We conclude that
the compartmental dynamics of CO, transport and storage are
very sensitive to changes in metabolic rate induced by exercise.

Effect of physical exercise training in patients with Chagas heart disease: study protocol for a randomized controlled trial (PEACH study)

Mendes, Fernanda de Souza Nogueira Sardinha; Sousa, Andréa
Silvestre; Souza, Fernando Cesar de Castro; Pinto, Vivian Liane Mattos;
Silva, Paula Simplicio; Saraiva, Roberto Magalhães; Xavier, Sergio
Salles; Veloso, Henrique Horta; Holanda, Marcelo; Costa, Andréa;
Carneiro, Fernanda Martins; Silva, Gilberto; Borges, Juliana Pereira;
Tibirica, Eduardo; Pinheiro, Roberta Olmo; Lara, Flávio Alves;
Hasslocher-Moreno, Alejandro Marcel; Brasil, Pedro; Mediano, Mauro
Felippe Felix.

Trials, December 2016, Vol. 17 Issue: Number 1 p1-11,
11p;

Abstract: The effects of exercise training on Chagas heart disease
are still unclear. This study aimed to evaluate the effect of exercise
training over functional capacity, cardiac function, quality of life,
and biomarkers in Chagas heart disease.                   The PEACH
study is a superiority randomized clinical trial which will include
subjects who meet the following criteria: Chagas heart disease with a
left ventricular ejection fraction below 45 % with or without heart
failure symptoms; clinical stability in the last 3 months; adherence to
clinical treatment; and age above 18 years. The exclusion criteria are:
pregnancy; neuromuscular limitations; smoking; evidence of non-chagasic
heart disease; systemic conditions that limit exercise practice or
cardiopulmonary exercise test; unavailability to attend the center
three times a week during the intervention period; and practitioners of
regular exercise. The intervention group will perform an exercise
training intervention three times per week during 6 months and will be
compared to the control group without exercise. Both groups will
undergo the same monthly pharmaceutical and nutritional counseling as
well as standard medical treatment according to the Brazilian consensus
on Chagas disease. The primary outcome is functional capacity based on
peak exercise oxygen consumption during cardiopulmonary exercise
testing. Secondary outcomes are: cardiac function; body composition;
muscle respiratory strength; microvascular reactivity; cardiac rhythm
abnormalities; autonomic function; biochemical; oxidative stress and
inflammatory biomarkers; and quality of life. Subjects will be
evaluated at baseline, and at 3 and 6 months after randomization.
Thirty patients will be randomly assigned into exercise or control
groups at a ratio of 1:1.                   Findings of the present
study will be useful to determine if physical exercise programs should
be included as an important additional therapy in the treatment of
patients with Chagas heart disease.

The effect of neoadjuvant chemotherapy and chemoradiotherapy on exercise capacity and outcome following upper gastrointestinal cancer surgery: an observational cohort study

West, M.; Loughney, L.;  Ambler, G.; Dimitrov, B.; Kelly, J.; Mythen, M.; Sturgess, R.;
Calverley, P.; Kendrick, A.; Grocott, M.; Jack, S..

BMC Cancer, December 2016, Vol. 16 Issue: Number 1 p1-8, 8p;

Abstract: In 2014 approximately 21,200 patients were diagnosed with oesophageal and
gastric cancer in England and Wales, of whom 37 % underwent planned
curative treatments. Potentially curative surgical resection is
associated with significant morbidity and mortality. For operable
locally advanced disease, neoadjuvant chemotherapy (NAC) improves
survival over surgery alone. However, NAC carries the risk of toxicity
and is associated with a decrease in physical fitness, which may in
turn influence subsequent clinical outcome. Lower levels of physical
fitness are associated with worse outcome following major surgery in
general and Upper Gastrointestinal Surgery (UGI) surgery in particular.
Cardiopulmonary exercise testing (CPET) provides an objective
assessment of physical fitness. The aim of this study is to test the
hypothesis that NAC prior to upper gastrointestinal cancer surgery is
associated with a decrease in physical fitness and that the magnitude
of the change in physical fitness will predict mortality 1 year
following surgery.                   This study is a multi-centre,
prospective, blinded, observational cohort study of participants with
oesophageal and gastric cancer scheduled for neoadjuvant cancer
treatment (chemo- and chemoradiotherapy) and surgery. The primary
endpoints are physical fitness (oxygen uptake at lactate threshold
measured using CPET) and 1-year mortality following surgery; secondary
endpoints include post-operative morbidity (Post-Operative Morbidity
Survey (POMS)) 5 days after surgery and patient related quality of life
(EQ-5D-5 L).                   The principal benefits of this study, if
the underlying hypothesis is correct, will be to facilitate better
selection of treatments (e.g. NAC, Surgery) in patients with
oesophageal or gastric cancer. It may also be possible to develop new
treatments to reduce the effects of neoadjuvant cancer treatment on
physical fitness. These results will contribute to the design of a
large, multi-centre trial to determine whether an in-hospital
exercise-training programme that increases physical fitness leads to
improved overall survival.