The second aim of this study was to describe the isokinetic muscle fatigue induced by high intensity OLDE and its recovery. Firstly, the absence of isometric KF MVC torque decrease confirms that our exercise only solicits the knee extensors and does not involve the knee flexors. Secondly, EMG RMS measured during KE MVCs shortly after exhaustion and during the recovery period was not altered by high intensity OLDE, confirming the results of a previous study [8]. Therefore, as a decrease in knee extensors force production capacity can be observed without concomitant changes in EMG signal, our data combined with the data of a previous study [8] suggest that EMG signal cannot be used to investigate dynamic exercise-induced muscle fatigue. The lack of changes in EMG signal is likely to be caused by a potentiation of the maximal evoked muscular wave (M-wave) induced by high intensity OLDE [8]. Finally, according to our hypothesis, isokinetic KE MVC torque quickly recovered and plateaued after exhaustion (within ~ 30 s at 60 and 100 deg/s, and within ~ 50 s at 140 deg/s). This quick recovery in torque production capacity is likely to be associated with recovery in both central and peripheral fatigue. This assumption is supported by one previous study in our laboratory demonstrating that not only peripheral and central fatigue, but also cortical and spinal excitability recovered shortly after exhaustion [8]. Froyd et al. [32] also demonstrated a significant recovery in skeletal muscle function within 1–2 minutes after completion of a one-leg isokinetic time trial performed at high intensity. Taking all together, these results demonstrate that to fully appreciate the extent of neuromuscular alterations induced by high intensity dynamic exercise, assessment of muscle fatigue must be performed within 30 s of cessation of the exercise.
Endurance performance (i.e. exercise duration > 1 min) is extensively studied in exercise physiology using cycling and/or running exercise (e.g. [1–4]). Despite being close to real competition events by involving the whole-body, the use of cycling and/or running exercise presents some important limitations to understand the role of the central nervous system (CNS) in the regulation of muscle fatigue and endurance performance. Indeed, as whole-body exercise involves greater systemic responses than isolated exercise [5], it is difficult to interpret some specific experimental manipulations aiming to understand CNS processes regulating muscle fatigue and endurance performance (e.g. manipulation of III-IV muscle afferents [6, 7]). Furthermore, due to the need to transfer the participant from the treadmill/bicycle to the ergometer, the true extent of muscle fatigue at exhaustion is underestimated [8], leading to inconclusive results on how peripheral (i.e. fatigue produced by changes at or distal to the neuromuscular junction [9]) and central (i.e. decrease in maximal voluntary activation level [9]) components of muscle fatigue might interact between each other’s (for review see [2, 9]). Therefore, due to the aforementioned limitations, the development of a new exercise model is required to better investigate the CNS processes regulating endurance performance.
Interval training is a type of training, which consists of alternating periods of high and low-intensity workouts interspersed with rest or relief periods. The high-intensity parts can be close to or in the anaerobic zone while the rest and relief periods involve lower intensity exercise. Interval training gets your rate up and burns more fat in less time than less intense forms of exercise. Here’s an example of an interval training routine:
In an earlier study, we found that in order to detect signs of OTS and distinguish them from normal training responses or FO, this method may be a good indicator not only of the recovery capacity of the athlete but also of the ability to normally perform the second bout of exercise.10 The test could, therefore, be used as an indirect measure of hypothalamic–pituitary capacity. It was hypothesised that on the NFO–OTS continuum, a hypersensitivity of the pituitary is followed by an insensitivity or exhaustion afterwards.10 22 Results from the present study confirm this hypothesis. The NFO athletes showed a very high response to the second exercise bout, at least in ACTH and PRL, whereas the OTS athletes showed suppression.
* Strength building is an expensive metabolic process. Although we see it as building muscle, our body is making global metabolic adaptations. It is upgrading its metabolic efficiency by synthesizing more enzymes to make metabolism more capable. This includes aerobic metabolism, anaerobic metabolism, gluconeogenesis, glycogen breakdown and transport, blood buffering agents, and of course new muscle fiber growth. All of this new synthesis is extremely metabolically expensive; that is why your body will not make these changes unless an intense stimulus is applied, and the organism is left undisturbed afterwards to make these changes.
Tracing the origins of Western MMB training suggests that the regular practice of movement-harmonizing exercises was embedded in ancient Greek culture.1 Herodotis. The history of Herodotus. New York (NY): Appleman and Company; 1885. [Google Scholar] Calisthenics in Greek means strength and beauty, a combination highlighted in Greek mythology and everyday life. This philosophy engendered sporting activities that were practiced to facilitate self-empowerment and prepare for events such as the Olympic Games or military actions.2 The Atlantic [Internet]. Cheever DW. The Gymnasium (1859). 2015 Aug 30 [cited 2015 Aug 30]. Available from: http://www.theatlantic.com/magazine/archive/1859/05/the-gymnasium/305407/. [Google Scholar] Today, Calisthenics refers to full-body movement exercises benefiting the body and mind by employing functional motions such as bending, stretching, twisting, kicking, jumping, push-ups, sit-ups, and squats.3 Greek Calisthenics Movement [Internet]. History. 2015 Jun 25 [cited 2015 Aug 30]. Available from: http://calisthenics.gr/en/index.html. [Google Scholar]
LSR, SBS, HV, NPA, JEI, UW and DS contributed to the conception and design of the study. LSR, SBS, HV and DS were responsible for the collection of the Generation 100 data in cooperation with colleagues at the Cardiac Exercise Research Group at the Norwegian University of Science and Technology, Norway. LSR, SBS and XT provided the data for analysis. LSR undertook the data analysis and drafted the manuscript. All authors provided critical insight and revisions to the manuscript. All authors read and approved the final version of the manuscript submitted for publication.

Remember Billy Blanks, the guy behind the Tae Bo craze? Now his son, Billy Blanks, Jr. is getting in on the family business too. Along with his wife, Sharon Catherine Blanks, Billy Jr. will help you learn various types of dance styles in this fun-packed DVD. The duo takes you through six 5-minute cardio workouts utilizing dance styles from all over the world: hip-hop, Bollywood, African, disco, country, and "old-school" cardio. It's designed for the whole family so kids can join in too!


Exercising in early adulthood is your first step toward staving off osteoporosis, a major risk factor for fractures and frailty. “Your bone density at 30 determines your bone density later in life,” explains Balachandran, whose research focuses on improving physical function in older adults. Sprinting, dancing, and strength training in your teens and 20s stimulate bone growth so you have a larger store to draw from as you age.
Jump up ^ Gomez-Pinilla F, Hillman C (January 2013). "The influence of exercise on cognitive abilities". Compr. Physiol. 3 (1): 403–428. doi:10.1002/cphy.c110063. ISBN 9780470650714. PMC 3951958. PMID 23720292. Abundant research in the last decade has shown that exercise is one of the strongest promoters of neurogenesis in the brain of adult rodents (97, 102) and humans (1,61), and this has introduced the possibility that proliferating neurons could contribute to the cognitive enhancement observed with exercise. In addition to BDNF, the actions of IGF-1 and vascular endothelial growth factor (VEGF) (54) are considered essential for the angiogenic and neurogenic effects of exercise in the brain. Although the action of exercise on brain angiogenesis has been known for many years (10), it is not until recently that neurovascular adaptations in the hippocampus have been associated with cognitive function (29). Exercise enhances the proliferation of brain endothelial cells throughout the brain (113), hippocampal IGF gene expression (47), and serum levels of both IGF (178) and VEGF (63). IGF-1 and VEGF, apparently produced in the periphery, support exercise induced neurogenesis and angiogenesis, as corroborated by blocking the effects of exercise using antibodies against IGF-1 (47) or VEGF (63).
You really listened to us in the prenatal visit and offered lots of useful ideas which helped us prepare fully for the birth. At the time of labor, you were totally perfect, with helpful words, actions, and emotional support. You were strong and soothing. I really got the birth I had hoped for, but couldn’t imagine I would have. Your support postpartum has been awesome with great breastfeeding tips, recovery advice, and more. ~ Kate, Boulder

P corresponds to the power expressed in watt (W), T the torque in newton meter (N·m) and the angular velocity in rad/s. Typical recordings of torque, position and EMG signals from the Vastus Lateralis (knee extensor) and Biceps Femoris (knee flexor) could be found in Fig 2. Fig 2 presents all signals previously mentioned for an isotonic resistance of 9 N·m (~ 16.7 W, panel A) and 37 N·m (~ 68.5 W, panel B). The inactivity of the Biceps Femoris during the flexion phase confirms that we were successful in creating a protocol on the dynamometer that isolates the knee extensor muscles during dynamic exercise, as in the exercise model originally proposed by Andersen et al. [10].
Walking was the most common exercise type in both training groups (Fig. 3). Compared to HIIT, MCT had a significantly higher proportion of sessions with walking and resistance training. Contrary, compared to MCT, HIIT had a higher proportion of sessions with cycling, combined endurance and resistance training, other types of endurance training (e.g. aerobic, treadmill), jogging, swimming and dancing. There were no group differences regarding cross-country skiing and domestic activities (e.g. housework, gardening) (Fig. 3).

It is well known that exercise in the older population may prevent several diseases [1–4]. Reduced physical activity impairs the quality of life in elderly people with Alzheimer's Disease [4], Parkinson's Disease [5], and Depressive Disorders [6]. Moreover, musculoskeletal, cardiopulmonary, and cerebrovascular decline are associated with poor physical fitness because of the cumulative effects of illness, multiple drug intake, fatigue, and bed rest [7, 8]. The effects of physical activity and exercise programs on fitness and health-related quality of life (HRQOL) in elderly adults have been widely studied by several authors [9–11]. De Vries et al. [11] conducted a meta-analysis focusing on elderly patients with mobility problems and/or multimorbidity. Eighteen articles describing a wide variety of actions were analyzed. Most used a multicomponent training program focusing on the combination of strength, balance, and endurance training. In 9 of the 18 studies included, interventions were supervised by a physical therapist. Intensity of the intervention was not reported and the duration of the intervention varied from 5 weeks to 18 months. This meta-analysis concluded that, considering quality of life, the exercise versus no-exercise studies found no significant effects. High-intensity exercise appears to be somewhat more effective in improving physical functioning than low-intensity exercise. These positive effects are of great value in the patient population but the most effective type of intervention remains unclear. Brovold et al. [7] recently examined the effects of high-intensity training versus home-based exercise programs using the Norwegian Ullevaal Model [12] on a group of over-65-year-olds after discharge from hospital. These authors based their study on the Swedish Friskis-Svettis model [13] which was designed by Johan Holmsater for patients with coronaropathy to promote their return to work and everyday activities and improve their prognoses. This model includes three intervals of high intensity and two intervals of moderate intensity, each one lasting for 5 to 10 minutes. Included in each is coordination. Exercises consist of simple aerobic dance movements and involve the use of both upper and lower extremities to challenge postural control [13]. Exercise intensity was adjusted using the Borg Rating of Perceived Exertion (RPE) Scale. Moderate intensity was set between 11 and 13, and high intensity was set between 15 and 17 on the Borg Scale.
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