Exercise for Cardiovascular Disease Prevention and Treatment From Molecular to Clinical, Part 1

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previous review [ 11 ]). While treadmill running and swimming are involuntary types

of exercise, wheel running is a voluntary exercise. These aerobic exercise models

with either voluntary or involuntary are extensively used to investigate the determi-

nants of exercise performance or interventional effects on various cardiovascular

pathological conditions, including chronic heart failure [ 11 ]. Treadmill running and

swimming are widely used as aerobic exercise in small animal rodents and in larger

animals. In moderate intensity or duration-controlled aerobic exercises, the duration

is performed in the acute or chronic mode of exercise in animals [ 1 , 3 ] leading to a

reduction in blood pressure in hypertension [ 50 ], an induction of physiological car-

diac hypertrophy, and cardiac remodeling [ 1 , 15 , 51 , 52 ].

3.2.1 Treadmill Running Exercise

Treadmill running exercise, an aerobic exercise, is a simple and yet effective modal-

ity widely used in cardiovascular researches. In this modality, several animals can

be simultaneously trained [ 3 ]. Treadmill running can be performed in a continuous

manner with a fixed or progressively increasing parameters such as inclination,

speed, and duration (minutes to hours) [ 1 , 18 , 39 , 43 ]. This exercise can be per-

formed in an interval training model allowing for high-intensity running bouts (suc-

cessive 4–8-min high-intensity treadmill running bouts at 85–90% of maximal

oxygen consumption (VO2max) achieved by running speeds of over 30 m per min

on a 25° inclined treadmill during the exercise sessions [ 22 , 42 , 43 , 51 ].

Interval running is widely used in studying exercise-induced animal cardiac

hypertrophy [ 1 , 34 ]. This can reduce the impact of the metabolic syndrome and

immensity of the effect depending on the intensity [ 22 , 42 ]. In other exercise

researches, the finding outcome suggested that compared to moderate intensity,

high-intensity exercise training was more beneficial in reducing cardiovascular risks

or heart failures in small rodents (rats, mice) with the metabolic syndrome [ 22 , 42 ].

This was linked to significantly improved VO2 max, endothelial function, blood

pressure, tissue metabolic parameters [ 22 ]. Increased mitochondrial density was

also reported in study applied this modality [ 42 ]. That data documented that a higher

training intensity is required to activate mitochondrial biogenesis and cardiac effi-

ciency in the mice heart [ 42 ]. Thus, the significance of training intensity is impor-

tant to trigger metabolic improvements in the myocardium, and it could promise a

potential therapeutic for heart failure patients [ 42 ]. In fact, not all exercise trainings

are equally beneficial, but high intensity training could be a vital therapeutic strat-

egy for treating patients who were once advised to have bed rest [ 53 ]. Endurance

treadmill training could be a safe and effective non-pharmacological means of

maintaining an optimal cardiac autonomic balance, improving cardiac electrical sta-

bility, and therefore eliminating risks of sudden cardiac death [ 5 ].

Overall, it is clearly accepted that treadmill running is a promising forced model

which can be used for aversive stimuli to induce appropriate exercise modality for

V.T. Thu et al.