Editing Exercise (section)

=== Other peripheral organs ===
[[File:Aerobic Anaerobic Exercise Adaptations.jpg|400px|thumb|Summary of long-term adaptations to regular aerobic and anaerobic exercise. Aerobic exercise can cause several central cardiovascular adaptations, including an increase in [[stroke volume]] (SV)<ref name=Exercise_SV>{{cite journal | vauthors = Wang E, Næss MS, Hoff J, Albert TL, Pham Q, Richardson RS, Helgerud J | title = Exercise-training-induced changes in metabolic capacity with age: the role of central cardiovascular plasticity | journal = Age | volume = 36 | issue = 2 | pages = 665–676 | date = April 2014 | pmid = 24243396 | pmc = 4039249 | doi = 10.1007/s11357-013-9596-x }}</ref> and maximal aerobic capacity ([[VO2 max|VO<sub>2</sub> max]]),<ref name=Exercise_SV /><ref name=AerobicMotorCapability>{{cite journal | vauthors = Potempa K, Lopez M, Braun LT, Szidon JP, Fogg L, Tincknell T | title = Physiological outcomes of aerobic exercise training in hemiparetic stroke patients | journal = Stroke | volume = 26 | issue = 1 | pages = 101–105 | date = January 1995 | pmid = 7839377 | doi = 10.1161/01.str.26.1.101 }}</ref> as well as a decrease in [[resting heart rate]] (RHR).<ref name=Exercise_RHR1>{{cite journal | vauthors = Wilmore JH, Stanforth PR, Gagnon J, Leon AS, Rao DC, Skinner JS, Bouchard C | title = Endurance exercise training has a minimal effect on resting heart rate: the Heritage Study | journal = Medicine and Science in Sports and Exercise | volume = 28 | issue = 7 | pages = 829–835 | date = July 1996 | pmid = 8832536 | doi = 10.1097/00005768-199607000-00009 | doi-access = free }}</ref><ref name=Exercise_RHR2>{{cite journal | vauthors = Carter JB, Banister EW, Blaber AP | title = Effect of endurance exercise on autonomic control of heart rate | journal = Sports Medicine | volume = 33 | issue = 1 | pages = 33–46 | year = 2003 | pmid = 12477376 | doi = 10.2165/00007256-200333010-00003 | s2cid = 40393053 }}</ref><ref name=Exercise_RHR3>{{cite journal| vauthors = Chen CY, Dicarlo SE |title=Endurance exercise training-induced resting Bradycardia: A brief review|journal=Sports Medicine, Training and Rehabilitation|date=January 1998|volume=8|issue=1|pages=37–77|doi=10.1080/15438629709512518}}</ref> Long-term adaptations to resistance training, the most common form of anaerobic exercise, include [[muscular hypertrophy]],<ref name=Exercise_Hypertrophy>{{cite journal | vauthors = Crewther BT, Heke TL, Keogh JW | title = The effects of a resistance-training program on strength, body composition and baseline hormones in male athletes training concurrently for rugby union 7's | journal = The Journal of Sports Medicine and Physical Fitness | volume = 53 | issue = 1 | pages = 34–41 | date = February 2013 | pmid = 23470909 }}</ref><ref name=Exercise_Hypertrophy2>{{cite journal | vauthors = Schoenfeld BJ | title = Postexercise hypertrophic adaptations: a reexamination of the hormone hypothesis and its applicability to resistance training program design | journal = Journal of Strength and Conditioning Research | volume = 27 | issue = 6 | pages = 1720–1730 | date = June 2013 | pmid = 23442269 | doi = 10.1519/JSC.0b013e31828ddd53 | s2cid = 25068522 | doi-access = free }}</ref> an increase in the [[physiological cross-sectional area]] (PCSA) of muscle(s), and an increase in [[neural drive]],<ref name=Exercise_Neuraldrive>{{cite journal | vauthors = Dalgas U, Stenager E, Lund C, Rasmussen C, Petersen T, Sørensen H, Ingemann-Hansen T, Overgaard K | display-authors = 6 | title = Neural drive increases following resistance training in patients with multiple sclerosis | journal = Journal of Neurology | volume = 260 | issue = 7 | pages = 1822–1832 | date = July 2013 | pmid = 23483214 | doi = 10.1007/s00415-013-6884-4 | s2cid = 848583 }}</ref><ref name=AnaerobicStrength>{{cite journal | vauthors = Staron RS, Karapondo DL, Kraemer WJ, Fry AC, Gordon SE, Falkel JE, Hagerman FC, Hikida RS | display-authors = 3 | title = Skeletal muscle adaptations during early phase of heavy-resistance training in men and women | journal = Journal of Applied Physiology | volume = 76 | issue = 3 | pages = 1247–1255 | date = March 1994 | pmid = 8005869 | doi = 10.1152/jappl.1994.76.3.1247 | s2cid = 24328546 }}</ref> both of which lead to increased [[muscular strength]].<ref name=Exercise_MuscularStrength>{{cite journal | vauthors = Folland JP, Williams AG | title = The adaptations to strength training : morphological and neurological contributions to increased strength | journal = Sports Medicine | volume = 37 | issue = 2 | pages = 145–168 | year = 2007 | pmid = 17241104 | doi = 10.2165/00007256-200737020-00004 | s2cid = 9070800 }}</ref> Neural adaptations begin more quickly and plateau prior to the hypertrophic response.<ref name=NeuralvsHypertrophy1>{{cite journal | vauthors = Moritani T, deVries HA | title = Neural factors versus hypertrophy in the time course of muscle strength gain | journal = American Journal of Physical Medicine | volume = 58 | issue = 3 | pages = 115–130 | date = June 1979 | pmid = 453338 }}</ref><ref name=NeuralvsHypertrophy2>{{cite journal | vauthors = Narici MV, Roi GS, Landoni L, Minetti AE, Cerretelli P | title = Changes in force, cross-sectional area and neural activation during strength training and detraining of the human quadriceps | journal = European Journal of Applied Physiology and Occupational Physiology | volume = 59 | issue = 4 | pages = 310–319 | year = 1989 | pmid = 2583179 | doi = 10.1007/bf02388334 | s2cid = 2231992 }}</ref>]]
Developing research has demonstrated that many of the benefits of exercise are mediated through the role of skeletal muscle as an endocrine organ. That is, contracting muscles release multiple substances known as [[myokine]]s which promote the growth of new tissue, tissue repair, and multiple anti-inflammatory functions, which in turn reduce the risk of developing various inflammatory diseases.<ref>{{cite journal | vauthors = Pedersen BK | title = Muscle as a secretory organ | journal = Comprehensive Physiology | volume = 3 | issue = 3 | pages = 1337–1362 | date = July 2013 | pmid = 23897689 | doi = 10.1002/cphy.c120033 | isbn = 978-0-470-65071-4 }}</ref> Exercise reduces levels of [[cortisol]], which causes many health problems, both physical and mental.<ref>{{cite journal | vauthors = Cohen S, Williamson GM | title = Stress and infectious disease in humans | journal = Psychological Bulletin | volume = 109 | issue = 1 | pages = 5–24 | date = January 1991 | pmid = 2006229 | doi = 10.1037/0033-2909.109.1.5 }}</ref> Endurance exercise before meals lowers [[Blood sugar level|blood glucose]] more than the same exercise after meals.<ref>{{cite journal | vauthors = Borer KT, Wuorinen EC, Lukos JR, Denver JW, Porges SW, Burant CF | title = Two bouts of exercise before meals, but not after meals, lower fasting blood glucose | journal = Medicine and Science in Sports and Exercise | volume = 41 | issue = 8 | pages = 1606–1614 | date = August 2009 | pmid = 19568199 | doi = 10.1249/MSS.0b013e31819dfe14 | s2cid = 207184758 | doi-access = free }}</ref> There is evidence that vigorous exercise (90–95% of [[VO2 max|VO<sub>2</sub> max]]) induces a greater degree of physiological [[cardiac hypertrophy]] than moderate exercise (40 to 70% of VO<sub>2</sub> max), but it is unknown whether this has any effects on overall morbidity and/or mortality.<ref>{{cite journal | vauthors = Wisløff U, Ellingsen Ø, Kemi OJ | title = High-intensity interval training to maximize cardiac benefits of exercise training? | journal = Exercise and Sport Sciences Reviews | volume = 37 | issue = 3 | pages = 139–146 | date = July 2009 | pmid = 19550205 | doi = 10.1097/JES.0b013e3181aa65fc | s2cid = 25057561 | doi-access = free }}</ref> Both aerobic and anaerobic exercise work to increase the mechanical efficiency of the heart by increasing cardiac volume (aerobic exercise), or myocardial thickness (strength training). [[Ventricular hypertrophy]], the thickening of the ventricular walls, is generally beneficial and healthy if it occurs in response to exercise.