recovery interval training density

Introduction: The current study aimed to investigate the responses to block- versus evenly-distributed high-intensity interval training (HIT) within a polarized microcycle. Methods: Twenty well-trained junior cross-country skiers (10 males, age 17.6 ± 1.5 and 10 females, age 17.3 ± 1.5) completed two, 3-week periods of training (EVEN and BLOCK) in a randomized, crossover-design study. In EVEN, 3 HIT sessions (5 × 4-min of diagonal-stride roller-skiing) were completed at a maximal sustainable intensity each week while low-intensity training (LIT) was distributed evenly around the HIT...

Previous studies have investigated the effects of high-intensity interval training (HIIT) on cardiorespiratory fitness and body composition in overweight populations. However, the additive effect of HIIT and hypoxia on health parameters is not clear. This study compared the effects of HIIT under hypoxic conditions on cardiometabolic function with that under normoxia in overweight Chinese young women. Methods: A double-blind randomized controlled experimental design was applied. Twenty-four sedentary overweight Chinese young women (weight: 68...

The purpose of the present study was to determine if acute responses in PGC-1α, VEGFA, SDHA, and GPD1-2 mRNA expression predict their associated chronic skeletal muscle molecular (SDH-GPD activity and substrate storage) and morphological (fibre-type composition and capillary density) adaptations following training. Skeletal muscle biopsies were collected from 14 recreationally active men (age: 22.0 ± 2.4 years) before (PRE) and 3 h after (3HR) the completion of an acute bout of sprint interval training (SIT) (eight 20-s intervals at ∼170% peak oxygen uptake work rate separated by 10 s of recovery)...

PURPOSE: Using a novel technique of high-density surface electromyography (HDEMG) decomposition and motor unit (MU) tracking, we compared changes in the properties of vastus medialis (VM) and vastus lateralis (VL) MUs following endurance (END) and high-intensity interval training (HIIT). METHODS: Sixteen men were assigned to an END or HIIT group (n=8 each) and performed six training sessions over 14 days. Each session consisted of 8-12×60s intervals at 100% peak power output (PPO) separated by 75s of recovery (HIIT) or 90-120min continuous cycling at ~65% VO2peak (END)...

Interval exercise typically involves repeated bouts of relatively intense exercise interspersed by short periods of recovery. A common classification scheme subdivides this method into high-intensity interval training (HIIT; 'near maximal' efforts) and sprint interval training (SIT; 'supramaximal' efforts). Both forms of interval training induce the classic physiological adaptations characteristic of moderate-intensity continuous training (MICT) such as increased aerobic capacity (V̇O2 max ) and mitochondrial content...

Successful cochlear implant performance requires adequate responsiveness of the auditory nerve to prolonged pulsatile electrical stimulation. Degeneration of the auditory nerve as a result of severe hair cell loss could considerably compromise this ability. The main objective of this study was to characterize the recovery of the electrically stimulated auditory nerve, as well as to evaluate possible changes caused by deafness-induced degeneration. To this end we studied temporal responsiveness of the auditory nerve in a guinea pig model of sensorineural hearing loss...

The purpose of this study was to compare three different intervals for a between sets rest period during a common isokinetic knee extension strength-testing protocol of twenty older Brazilian men (66.30 ± 3.92 yrs). The volunteers underwent unilateral knee extension (Biodex System 3) testing to determine their individual isokinetic peak torque at 60, 90, and 120° ·s-1. The contraction speeds and the rest periods between sets (30, 60 and 90 s) were randomly performed in three different days with a minimum rest period of 48 hours...

The aim of the study was to investigate the influence of training load and exercise mode on heart rate variability and heart rate recovery (HRR) in healthy individuals. The subjects were divided into three groups: sedentary (SED), resistance trained (RT) and aerobically trained (RT). Resting and postmaximal exercise RR intervals were recorded on supine and seated position, respectively. The HRV indices calculated in the resting position were RMSSD and LF and HF power densities. The following HRR indices were calculated throughout the 5-minute postmaximal recovery period: semi-logarithmic regression analysis of the first 30 s (T30); absolute difference between the peak and 60 s HR (HRR(60s)); and mono-exponential time constant of HRR (HRRτ)...

In the US, 34% of adults currently meet the criteria for the metabolic syndrome defined by elevated waist circumference, plasma triglycerides (TG), fasting glucose and/or blood pressure, and decreased high-density lipoprotein cholesterol (HDL-C). While these cardiometabolic risk factors can be treated with medication, lifestyle modification is strongly recommended as a first-line approach. The purpose of this review is to focus on the effect of physical activity interventions and, specifically, on the potential benefits of incorporating higher intensity exercise...

The effect of an alteration from regular endurance to interval (10-20-30) training on the health profile, muscular adaptations, maximum oxygen uptake (Vo(2max)), and performance of runners was examined. Eighteen moderately trained individuals (6 females and 12 males; Vo(2max): 52.2 ± 1.5 ml·kg(-1)·min(-1)) (means ± SE) were divided into a high-intensity training (10-20-30; 3 women and 7 men) and a control (CON; 3 women and 5 men) group. For a 7-wk intervention period the 10-20-30 replaced all training sessions with 10-20-30 training consisting of low-, moderate-, and high-speed running (<30%, <60%, and >90% of maximal intensity) for 30, 20, and 10 s, respectively, in three or four 5-min intervals interspersed by 2 min of recovery, reducing training volume by 54% (14...

OBJECTIVE: Exercise capacity strongly predicts survival and aerobic interval training (AIT) increases peak oxygen uptake effectively in cardiac patients. Usual care in Norway provides exercise training at the hospitals following myocardial infarction (MI), but the effect and actual intensity of these rehabilitation programmes are unknown. DESIGN: Randomized controlled trial. SETTING: Hospital cardiac rehabilitation. SUBJECTS: One hundred and seven patients, recruited two to 12 weeks after MI, were randomized to usual care rehabilitation or treadmill AIT...

OBJECTIVE: To assess the effect of pain-free treadmill training on changes of plasma fibrinogen, haematocrit, lipid profile, and walking ability in patients with claudication. DESIGN: Randomized control trial. METHODS: Sixty-eight patients with peripheral obstructive arterial disease and intermittent claudication (Fontaine stage II) were randomly assigned into the treadmill training (repetitive intervals to onset of claudication pain, three times a week) or a control group (no change in physical activity) over 3 months...

BACKGROUND: Patellar tendinopathy is a major problem for many athletes, especially those involved in jumping activities. Despite its frequency and negative impact on athletic careers, no evidence-based guidelines for management of this overuse injury exist. Since functional outcomes of conservative and surgical treatments remain suboptimal, new diagnostic and therapeutic strategies have to be developed and evaluated. Extracorporeal shockwave therapy (ESWT) appears to be a promising treatment in patients with chronic patellar tendinopathy...

RATIONALE: In the present study we explored the mechanisms behind excitation-contraction (EC) coupling defects in cardiomyocytes from mice with type-2 diabetes (db/db). OBJECTIVE: We determined whether 13 weeks of aerobic interval training could restore cardiomyocyte Ca(2+) cycling and EC coupling. METHODS AND RESULTS: Reduced contractility in cardiomyocytes isolated from sedentary db/db was associated with increased diastolic sarcoplasmic reticulum (SR)-Ca(2+) leak, reduced synchrony of Ca(2+) release, reduced transverse (T)-tubule density, and lower peak systolic and diastolic Ca(2+) and caffeine-induced Ca(2+) release...

BACKGROUND: Hip fracture creates a worldwide morbidity, mortality and economic burden. After surgery, many patients experience long-term disability or die as a consequence of the fracture. A fracture is a major risk factor for a subsequent fracture, which may occur within a short interval. METHODS: A literature search on post-fracture management of patients with hip fracture was performed on the Medline database. Key experts convened to develop a consensus document...

Noninvasive imaging techniques have been used to assess pulmonary edema following exercise but results remain equivocal. Most studies examining this phenomenon have used male subjects while the female response has received little attention. Some suggest that women, by virtue of their smaller lungs, airways, and diffusion surface areas may be more susceptible to pulmonary limitations during exercise. Accordingly, the purpose of this study was to determine if intense normobaric hypoxic exercise could induce pulmonary edema in women...

We tested the hypothesis that intense short duration hypoxic exercise would result in an increase in extravascular lung water (EVLW), as evidenced by an increase in lung density. Using computed tomography (CT), baseline lung density was obtained in eight highly trained male cyclists (mean +/- SD: age = 28 +/- 8 years; height = 180 +/- 9 cm; mass = 71.6 +/- 8.2 kg; VO2max= 65.0 +/- 5.2 ml kg min(-1)). Subjects then completed an intense hypoxic exercise challenge on a cycle ergometer and metabolic data, HR and %S(p)O2 were recorded throughout...

Intermittent, chronically delivered electrical stimulation of the vagus nerve (VNS) is an FDA-approved procedure for the treatment of refractory complex/partial epilepsy in humans. Stimulation of the vagus has also been shown to enhance memory storage processes in laboratory rats and human subjects. Recent evidence suggests that some of these effects of VNS may be due to the activation of neurons in the nucleus locus coeruleus resulting in the release of norepinephrine (NE) throughout the neuraxis. Because antagonism of NE systems has been shown to delay recovery of function following brain damage, it is possible that enhanced release of NE in the CNS may facilitate recovery of function...

We compared the effects of three models of permanent ischemia, as well as cortical aspiration, on behaviour and brain morphology. Rats received a stroke either by devascularization or by two different procedures of medial cerebral artery occlusion (MCAO; small vs. large). Animals were trained in a reaching task, forepaw asymmetry, forepaw inhibition, sunflower seed task and tongue extension. Behaviour was assessed 1 week after the lesion and at 2-week intervals for a total of 9 weeks. One week after the surgery all animals were severely impaired on all tasks and although they improved over time they only reached preoperative base lines on tongue extension...

BACKGROUND: A gradual worsening of autonomic control of cardiovascular function accompanies the progression of heart failure. Exercise training modulates autonomic balance, and may affect the prognosis of the disease. AIMS: The sympathovagal balance was studied after 3 months of low-intensity rehabilitation compared with conventional therapy in 45 patients with heart failure (52% ischemic, 48% idiopathic), of whom 30 underwent rehabilitation and 15 did not. In 11 rehabilitated patients we also studied the effects on autonomic profile of 6 additional months of home-based training...