Endurance training

Image taken from: patrickamadeu.com^[26]

What is endurance training?

Endurance training or aerobic training is building the body to endure repetitions of exercise without terminating quickly. Endurance training requires the use of several muscles whilst performing a single activity (figure 1 and 2) to enhance the cardiovascular and respiratory systems (figure 3) ^[1],

 

Figure 1 and 2: Activities of endurance training utilising more than one muscle whilst performing a single activity enhancing personal aerobic exercise endurance. | Image taken from: www.lifespanfitness.com/fitness/resources/articles/rowing-machine-benefits-for-cardiovascular-fitness ^[27],[28]

Figure 3: Various short-term and long-term beneficial systemic and cardiac effects on the body during exercise | Image from Dizon L.A et. al. 2013^[29]

 

The systems are enhanced by the VO2 max (maximal oxygen uptake during exercise) being increased allowing your body to use oxygen efficiently during exercise [figure 4], with regular endurance exercise your body adjusts to meet the energy your body needs building a healthier body as shown in figure 5 ^[2] this can benefit you long term and grant you a longer life ^[3] as oppose to diabetes which may result in early death ^[4].

Figure 4: VO2 max increasing continuously during certain speeds over the course of 12 months of endurance training showing endurance exercise takes an effect on increasing VO2 max in an individual ^[5]. Substantial amount of oxygen needs to reach the muscles in use in order for the ATP to be maintained towards aerobic mechanisms hence the VO2 max increasing as endurance to the speed increases. ^[2] Image taken from slideplayer.com/slide/6111947/ ^[30]

 

Figure 5: Cardiac output increasing as speed on the treadmill increases which demonstrates the endurance the body builds over time by performing exercise.  Heart rate is speed of heart beat per unit time and stroke volume is the amount of blood being pumped from the left/right ventricle per minute combining to make the cardiac output, when exercising your operating muscles require your heart to pump faster for increased blood flow concluding to your stroke volume increasing by the return of blood volume to the lungs for oxygen as more is in need, cardiac output therefore displays an increase. ^[6] | Image taken from slideplayer.com/slide/6111947/ ^[30]

 

What training is classified as endurance exercise?

Figure 6: Variety of activities of what endurance training involves.

To perform some of these exercises you do not need equipment which means you’re not required to make any financial commitments at the gym if you do not want to.

 

How does endurance training help with Type 2 Diabetes Mellitus (T2DM)?

The issue is that your body has glucose build up (hyperglycaemia) due to the insulin in your body not being used efficiently or a small-scale being produced which isn’t enough to be processed (figure 7). Endurance exercise can minimise the amount of glucose in your blood. When exercising your muscles can take up glucose without the need of insulin ^[7] which is the prime issue of glucose build up, this means your blood glucose levels decrease without the use of medicine, this remedy is the cheapest and most beneficial and you’re completely in control of it, in order to achieve this you must engage in physical activity 150 min/week ^[8].

 

Figure 7: Demonstration of how hyperglycaemia initiates in the body. | Source: Sutton M.T, Bonfield T.L 2014 ^[31]

Many risks are associated with T2DM, with long term exercise the natural history of the risk can be prevented ^[9]. Just one session of endurance training can reduce hyperglycaemia for the upcoming 24 hours in an individual ^[10] which displays the significant impact one endurance training session can have on your health, let alone fulfilling the requirement of 150min/week which can allude to a life changing impact.

 

How does endurance training help with hypertension (high blood pressure)?

 One of the risks for T2DM is hypertension. When one is jogging, swimming or cycling there’s a need for skeletal muscles (muscles attached to bones) to contract, to do this continuously muscles need oxygen delivered to them and this is done by increasing stroke volume which increases blood flow (figure 8), the arterial pressure decreases concluding the blood pressure to lower  ^[11].  Blood pressure is lowered up to 22 hours after exercise as shown in figure 9 ^[12], this is remarkable as the effect of the pressure lowering doesn’t just last during exercise, it continues on even when your in your resting state so you may be working out for 30 minutes but your body is rewarding you for a further 22 hours ^[13] furthermore, the additional minutes you engage in exercising is accompanied with a higher reduction in both, systolic pressure (when the heart contracts and pumps the blood out) and diastolic pressure(when the heart is relaxing between beats and the chambers are refilling with blood)  ^[14], so if you have the energy or if you’re willing to work out for a bit longer than usual – know that it will have a POSITIVE impact on your blood pressure, every extra minute is worth it and your body will pay you in better health.

Figure 8: Hemoglobin/blood flow increasing as the maximal oxygen uptake is being delivered to the muscles in use whilst engaging in exercise  ^[11]. Limited amount of oxygen is stored in the blood and active skeletal muscles are in need of oxygen, so an increase in hemoglobin is known to transport more oxygen to the working muscles. Production of ATP is made aerobically rooting from the mitochondria with an entail of oxygen and indisputably, a valuable amount of ATP is needed for endurance exercise.  ^[11] | Image taken from Joyner M.J, Casey D.P, 2015 ^[32]

 

Figure 9: Blood pressure decreasing up to 20 hours after exercise | Image taken from www.quora.com/How-is-hypertensive-blood-pressure-different-from-blood-pressure-due-to-physical-activity-or-exercise ^[33]

 

How does endurance training help with atherosclerosis (disease where arteries narrow due to the build up of plaque ^[24])?

Unfortunately, many risks are associated with T2DM, atherosclerosis being one of them ^[15], endurance training can reduce the risks of atherosclerosis development ^[16] at a certain level by decreasing the thickness of arterial walls as presented in figure 10 ^[17], blocked arteries due to the accumulation of fatty substances ^[18]  block the flawless flow of blood through the narrow arteries as presented in figure 11. Low-density lipoprotein (LDL) is bad cholesterol that builds up in the artery ^[19] and High-density Lipoprotein (HDL) is good cholesterol that reduces the risk of developing heart disease ^[20], endurance training exerts HDL and reduces LDL so to reduce LDL more endurance exercise must be practiced upon to gain that HDL^[21] and the body will show a change in atherosclerosis (Table 1). Marathon runners show a reduction to cardiovascular risk factors ^[22], which is a prime example to how advantageous the exercise can be as illustrated by humans that engage in endurance training as a living.

 

Figure 10: Diameter of carotid arteries of elite squash players who engage in endurance exercise ^[25] showing a significant difference of widening of the diameter. ^[17] | Image taken from Thigssen D.H et. al., 2012^[17]

 

Figure 11: The artery consists of 3 layers: intima which is made of endothelial cells in contact with the bloodstream, media: the middle layer and the outermost layer: adventitia. The endothelial cells which produces nitric oxide helps evert spasms of the smooth muscle cells (from the media) and keeps the arteries open therefore improving blood flow. Plaque builds up in the media causing the artery to be augment and decreased blood flow, nevertheless nitric oxide can be produced by endothelial cells by exercise to try and reverse the effect ^[34],[35] | Image taken from https://www.verywellhealth.com/what-is-atherosclerosis-1745908^[34]

 

Table 1: ‘Theintima-media thickness test (IMT) was taken, the “effect” column indicates where or not higher fitness is related to lower arterial IMT (+) or no difference shown indicated in arterial IMT (~) CA, carotid artery; FA, femoral artery; BA, brachial artery.’^[17] | Image taken from Thigssen D.H et. al., 2012 ^[17]

First author	n	Age (years)	Fitness measure	Artery	Effect
Hagg [50]	29	20–40	Exercise test	CA	+
Rauramaa [51]	163	50–60	Exercise test	CA	+
Sandrock [52]	101	64±5	Exercise test	CA	+
Lee [53]	9871	40–81	Exercise test	CA	+
Lakka [57]	854	42–60	Exercise test	CA	+
Moreau [67]	173	20–79	Exercise history	FA	+
Rowley [61]	29	22±3	Exercise history	CA-BA-FA	+
Moreau [60]	77	48–80	Exercise history	CA-FA	+ (FA), ~(CA)
Tanaka [58]	137	18–77	Exercise history	CA	~
Popovic [59]	150	20–40	Exercise history	CA	~
Hamer [54]	530	63±6	Walking speed	CA	+
Elbaz [55]	2572	65–85	Walking speed	CA	+
Bertoni [56]	6482	45–84	Walking speed	CA	+
Juonala [42]	1809	24–39	Questionnaire	CA	+
Stensland-Bugge [43]	6408	25–84	Questionnaire	CA	+ (men+higher age)
Stensland-Bugge [44]	3128	25–84	Questionnaire	CA	+ (men)
Luedemann [45]	1632	45–70	Questionnaire	CA	+ (but not in smokers)
Folsom [46]	14430	45–64	Questionnaire	CA	+
Nordstrom [47]	500	40–60	Questionnaire	CA	+ (dose-dependent)
Yamada [49]	149	54±12	Questionnaire	CA-FA	~
Kozakava [87]	495	44±8	Accelerometry	CA	+
Kozakova [88]	432	43±8	Accelerometry	CA	~

Many diagnosed with T2DM are not active and neglect exercise due to laziness, contribution to exercise will improve your blood glucose levels and essentially discourage or obstruct T2DM ^[1]. Exercise as simple as walking 150 min/week as oppose to walking less than 60 min/week can reduce the risk of T2DM by 60% ^[8] that could be a 21 minute walk a DAY, 10 minutes to get to somewhere and 10 minutes back without sweating or tiring yourself out, on the other hand you could also engage in 50 minutes of training for 3 days a week which gives you 4 days of rest and you’ve hit your goal of 150 min/week.

With the expected figure of TD2M to increase to 439 million by 2030 ^[23]  let’s make sure that you are not accounted for one of them.

 

Written by Almas Munshi.

 

References:

1. Colberg S, Sigal R, Fernhall B, Regensteiner J, Blissmer B, Rubin R et al. Exercise and Type 2 Diabetes: The American College of Sports Medicine and the American Diabetes Association: joint position statement executive summary. Diabetes Care [Internet]. 2010;33(12):2692-2696. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2992214/
2. Evans D. Cardiovascular Adaptations to Exercise and Training. Veterinary Clinics of North America: Equine Practice [Internet]. 1985;1(3):513-531. Available from: https://www.ncbi.nlm.nih.gov/pubmed/3877552
3. Reimers C, Knapp G, Reimers A. Does Physical Activity Increase Life Expectancy? A Review of the Literature. Journal of Aging Research [Internet]. 2012;2012:1-9. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3395188/
4. Asif M. The prevention and control the type-2 diabetes by changing lifestyle and dietary pattern. Journal of Education and Health Promotion [Internet]. 2014;3(1):1. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3977406/
5. Stromme S, Ingjer F, Meen H. Assessment of maximal aerobic power in specifically trained athletes. Journal of Applied Physiology [Internet]. 1977;42(6):833-837. Available from: https://www.researchgate.net/publication/22274324_Assessment_of_maximal_aerobic_power_in_specifically_trained_athletes
6. CARMICHAEL J. Why Does Stroke Volume Increase During Exercise? [Internet]. 2018 [cited 15 November 2018]. Available from: https://www.livestrong.com/article/403152-why-does-stroke-volume-increase-during-exercise/?ajax=1&is=1
7. Lisa M. Leontis RN A. Type 2 Diabetes and Exercise [Internet]. EndocrineWeb. 2018 [cited 15 November 2018]. Available from: https://www.endocrineweb.com/conditions/type-2-diabetes/type-2-diabetes-exercise
8. Wu Y, Ding Y, Tanaka Y, Zhang W. Risk Factors Contributing to Type 2 Diabetes and Recent Advances in the Treatment and Prevention. International Journal of Medical Sciences [Internet]. 2014;11(11):1185-1200. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4166864/#B180
9. Balducci S, Iacobellis G, Parisi L, Di Biase N, Calandriello E, Leonetti F et al. Exercise training can modify the natural history of diabetic peripheral neuropathy. Journal of Diabetes and its Complications [Internet]. 2006;20(4):216-223. Available from: https://www.ncbi.nlm.nih.gov/pubmed/16798472
10. van Dijk J, Manders R, Tummers K, Bonomi A, Stehouwer C, Hartgens F et al. Both resistance- and endurance-type exercise reduce the prevalence of hyperglycaemia in individuals with impaired glucose tolerance and in insulin-treated and non-insulin-treated type 2 diabetic patients. Diabetologia [Internet]. 2012;55(5):1273-1282. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3331783/
11. Joyner M, Casey D. Regulation of Increased Blood Flow (Hyperemia) to Muscles During Exercise: A Hierarchy of Competing Physiological Needs. Physiological Reviews [Internet]. 2015;95(2):549-601. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4551211/
12. Pescatello LS e. American College of Sports Medicine position stand. Exercise and hypertension. – PubMed – NCBI [Internet]. Ncbi.nlm.nih.gov. 2004 [cited 15 November 2018]. Available from: https://www.ncbi.nlm.nih.gov/pubmed/15076798
13. Ishikawa-Takata K. How much exercise is required to reduce blood pressure in essential hypertensives: a dose–response study. American Journal of Hypertension [Internet]. 2003;16(8):629-633. Available from: https://academic.oup.com/ajh/article/16/8/629/199247
14. Kelley G, Kelley K. Aerobic Exercise and Resting Blood Pressure in Older Adults: A Meta-analytic Review of Randomized Controlled Trials. The Journals of Gerontology Series A: Biological Sciences and Medical Sciences [Internet]. 2007;56(5):M298-M303. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2094526/
15. Watson KE e. Atherosclerosis in type 2 diabetes mellitus: the role of insulin resistance. – PubMed – NCBI [Internet]. Ncbi.nlm.nih.gov. 2018 [cited 15 November 2018]. Available from: https://www.ncbi.nlm.nih.gov/pubmed/14740074
16. Palmefors H, DuttaRoy S, Rundqvist B, Börjesson M. The effect of physical activity or exercise on key biomarkers in atherosclerosis – A systematic review. Atherosclerosis [Internet]. 2014;235(1):150-161. Available from: https://www.sciencedirect.com/science/article/pii/S0021915014002263
17. Thijssen D, Cable N, Green D. Impact of exercise training on arterial wall thickness in humans. Clinical Science [Internet]. 2011;122(7):311-322. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3233305/
18. Frayn K. Metabolic Regulation. 2nd ed. Somerset: Wiley; 2013.
19. Linton M, Yancey P, Davies S, Jerome W, Linton E, Vickers K. The Role of Lipids and Lipoproteins in Atherosclerosis [Internet]. Ncbi.nlm.nih.gov. 2015 [cited 15 November 2018]. Available from: https://www.ncbi.nlm.nih.gov/books/NBK343489/
20. Vergeer M, Holleboom A, Kastelein J, Kuivenhoven J. The HDL hypothesis: does high-density lipoprotein protect from atherosclerosis?: Fig. 1. Journal of Lipid Research. 2010;51(8):2058-2073.
21. Wang Y, Xu D. Effects of aerobic exercise on lipids and lipoproteins. Lipids in Health and Disease [Internet]. 2017;16(1). Available from: https://lipidworld.biomedcentral.com/articles/10.1186/s12944-017-0515-5
22. SchwartzRS, KrausSM, SchwartzJG, etal. Increasedcoronaryarteryplaquevolumeamongmalemarathonrunners. MoMed2014;111:85-90. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6179497/
23. Chen L, Magliano DJ, Zimmet PZ. The worldwide epidemiology of type 2 diabetes mellitus-present and future perspectives. Nat Rev Endocrinol. 2011;8(4):228–236. Available from: PubMed
24. Insull W. The Pathology of Atherosclerosis: Plaque Development and Plaque Responses to Medical Treatment. The American Journal of Medicine [Internet]. 2009;122(1):S3-S14. Available from: https://www.amjmed.com/article/S0002-9343(08)01017-6/fulltext
25. Girard O. Specific incremental test in elite squash players. British Journal of Sports Medicine [Internet]. 2005;39(12):921-926. Available from: https://bjsm.bmj.com/content/39/12/921
26. HOW TO SUPPLEMENT: TIPS TO BOOST YOUR ENDURANCE TRAINING – Patrick Amadeu – Lifestyle Systems [Internet]. Patrick Amadeu – Lifestyle Systems. 2018 [cited 16 November 2018]. Available from: https://patrickamadeu.com/how-to-supplement-tips-to-boost-your-endurance-training/
27. Benefits of Rowing | Benefits of a Rowing Machine [Internet]. Lifespanfitness.com. 2018 [cited 16 November 2018]. Available from: https://www.lifespanfitness.com/uk/fitness/resources/articles/rowing-machine-benefits-for-cardiovascular-fitness?___store=uk&__from_store=uk
28. Elliptical vs Treadmill | Elliptical Machine Benefits [Internet]. Lifespanfitness.com. 2018 [cited 16 November 2018]. Available from: https://www.lifespanfitness.com/fitness/resources/articles/elliptical-vs-treadmill-benefits-comparison
29. Dizon L, Seo D, Kim H, Kim N, Ko K, Rhee B et al. Exercise perspective on common cardiac medications. Integrative Medicine Research [Internet]. 2013;2(2):49-55. Available from: https://www.researchgate.net/publication/257746053_Exercise_perspective_on_common_cardiac_medications
30. Chapter 10 Adaptations to Aerobic and Anaerobic Training. – ppt download [Internet]. Slideplayer.com. 2018 [cited 16 November 2018]. Available from: http://slideplayer.com/slide/6111947/
31. Sutton M, Bonfield T. Stem Cells: Innovations in Clinical Applications. Stem Cells International [Internet]. 2014;2014:1-9. Available from:https://www.researchgate.net/publication/264793336_Stem_Cells_Innovations_in_Clinical_Applications
32. Joyner M, Casey D. Regulation of Increased Blood Flow (Hyperemia) to Muscles During Exercise: A Hierarchy of Competing Physiological Needs. Physiological Reviews [Internet]. 2015;95(2):549-601. Available from: https://www.physiology.org/doi/full/10.1152/physrev.00035.2013
33. How is hypertensive blood pressure different from blood pressure due to physical activity or exercise? [Internet]. Quora. 2018 [cited 16 November 2018]. Available from: https://www.quora.com/How-is-hypertensive-blood-pressure-different-from-blood-pressure-due-to-physical-activity-or-exercise
34. Fogoros R. How Atherosclerosis Can Be Treated [Internet]. Verywell Health. 2018 [cited 16 November 2018]. Available from: https://www.verywellhealth.com/what-is-atherosclerosis-1745908
35. Publishing H. Exercise and your arteries – Harvard Health [Internet]. Harvard Health. 2018 [cited 16 November 2018]. Available from: https://www.health.harvard.edu/newsletter_article/Exercise_and_your_arteries