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This article will teach you how to make sure youll see your great, great grand children.

This is one of the many things I have learned from my good friend Carl Lanore, whose radio show, Super Human Radio, I have been following for years before I became what Carl once called "semi-famous": We, that is humans in general and researchers in particular, tend to focus way too much on the sophisticated, the innovative and the revolutionary stuff, when oftentimes the answer to ostensibly open question is lying openly before our eyes. Athletics and bodybuilding, is one of these areas, where practitioners have been doing everything right for decades... and what was their reward? World-records and mind-boggling physiques, for example.

This is yet by no means the only example. The "paleo movement", as bizarre and disfigured as it may have become does still exemplify that the same can be said of "healthy eating", as well.
There have always been people who (instinctively?) knew how to do it - hell, even the hailed Mediterranean Diet is no invention of brainy scientists (certainly not of dumb dietitians). And when we are honest, we dont need websites like Longecity and tons of useless supplements to make the most of our genetic longevity potential: We all know what we should do, but unfortunately, many of us tend to forget that we dont do what it takes to join the ranks of those people about whom Marilynn Larkin wrote in ther 1999 paper "Centenarians point the way to healthy ageing" (Larkin. 1999).

Todays SuppVersity article is an homage to these people and the well-known but often overlooked research on what helps and hinders us from joining the ranks of people like Betsy Baker (supposedly 113, when she died in 1955), Marie-Louise Meilleur (supposedly 117, when she died in 1988) or Jiroemon Kimura (supposedly 116, when he died last year). I mean, they must have done many things right and only few things wrong, right? Based on the contemporary evidence, Ive compiled a list of rules. I guess, neither Betsy or Marie-Louise, nor Jiroemon will have followed all of them to the "T", but hey, this leaves room for you to decide whether youd rather indulge in one or another passion or stick to all of them to the "T" top Marie-Louises 117 or Jiroemons 116 years of age :-)

• Use the available medical care to your advantage: Within the health and fitness community, the things our regular doctors can do for us have gotten a surprisingly bad rep. It does however stand out of question that the availability and use of modern medicine is one of the cornerstones of the ever-increasing longevity in centennials and other healthy elderly. From basic treatments to complicated operations, all these things the availability of which we usually take for granted has helped us (and the living centenarians) to do what Thomas Perls calls "to ‘compress morbidity’ and live most of our lives in good health, with only a short period of ill health at the end." (Perls. 1999)

  Figure 1: Luckily, your place of birth is not the only determinant of life expectancy; map depicts life expectancy (in years) at birth (created by Panagiotis V. Lazaridis based on WHO & CIA data in 2008)

  At first this may contradict findings Engberg et al. present in a paper with data from a 29-year follow-up of hospitalizations among 40 000 Danes born in 1905, but in the end, it should be obvious that the low hospitalization rates, the Danish researchers observed in centenarians and almost centenarians were rather a consequence than a cause of their longevity and probably also due to timely non-stationary medical interventions, when one of them actually got sick (Engberg. 2009)
• Dont smoke, or quit smoking: I know this should be obvious, but I guess too many people still believe that they must belong to the lucky few Lewin and Crimmins, the authors of a recent paper with the intruiging title "Not All Smokers Die Young: A Model for Hidden Heterogeneity within the Human Population." (Lewin. 2014) are interested in. Contrary to these (allegedly) genetic outliers, the majority of us will suffer a significant reduction in life expectancy. Estimations of the number of years youll lose range from a handful of years to up to 25% (Rogers. 1991). For a US citizen the latter would equal almost 16 years! Years, of which Susan T. Stewart et al. (2009) say that the average 18-year-old may reclaim 3.76 life-years and, more importantly, 5.16 quality-adjusted years, in which he or she is not hospitalized and wasting away, if they managed to avoid the getting overweight / obese instead.

• In fact, the increase in BMI after smoking sessation "overwhelmed the positive effects of declines in smoking in multiple scenarios" Stewart et al. calculated and reduced the benefits for an 18-year old to 0.71 years or 0.91 (Stewart. 2009).
  
  But dont worry, other studies report much more beneficial effects. Taylor et al. (2002), for example, estimate that the life expectancy among smokers who quit at age 35 will exceeded that of continuing smokers by 6.9 to 8.5 years for men and 6.1 to 7.7 years for women. And in spite of the fact that early smokers will obviously realize greater gains in life expectancy, even those even those who quit much later in life gained some benefits: among smokers who quit at age 65 years, men gained 1.4 to 2.0 years of life, and women gained 2.7 to 3.7 years.
• Avoid drinking alcohol in amounts >0.5 glasses of wine per day: Notwithstanding the overcited epidemiological evidence which suggests that a moderate alcohol consumption will have beneficial effects on your life-expectancy, the margin between "just enough" and "already too much" is simply too narrow for me to suggest you drink more than the literal half glass of wine thats supposed to lower the all-cause mortality risk of women by ~20-25% (Streppel. 2009).
  
  

  Table 1: Relative Risk for Major Chronic Disease Categories, by Gender and Average Drinking Category (Rehm. 2002)

  A high(er) level of alcohol consumption, on the other hand, has been found to be associated with a higher risk of hypertension, alcoholic cardiomyopathy, cancer, cerebrovascular events and dementia (Kloner. 2007) - a fact that should remind you that (a) the evidence regarding the possible health benefits of alcohol is uncertain, and that (b) alcohol may not benefit everyone who drink. Theoretically, genetic polymorphisms that make alcohol the panacea for one, could turn an in innocent glass of wine into a deadly poison for someone else (Hashimoto. 2002).
  
  And just in case the ambiguity of data aint reason enough for you to let go of all alcoholic beverages on at least360 of 365 days of the year, the data in Table 1 may convince you.
  
  If you take a closer look at "Drinking Category I", where youll find all the women who consume 0–19.99 g pure alcohol and all the men who consume 0–39.99 g pure alcohol every day (a glass of wine has ~13g), you will see that alcohol increases the risk of liver cirrhosis by 26%, hypertensive diseases and other CVD by 40% and 50%, is associated with 34% and 23% higher risk of epilepsy for women and men, respectively and increases the risk of all cancers esp. those of the esophagus (+80%) significantly.
  
  I am not sure about you, but for me this alone would be enough to get my sleep, diet and exercise regimen in check instead of trying to use alcohol as a means to reduce my CVD risk.
• Attend to relationships and friends: Individuality has become on of the / the (choose for yourself) highest good(s) of Western civilization and few people are aware that we are paying a very high price for that. The influence of social relations on mortality is, after all, well documented. A meta-analysis of 148 studies (308,849 participants followed for an average of 7.5 years) confirms that the quality of our social networks significantly predicts mortality (Holt-Lunstad. 2010).

  Figure 2: Weighted avg. effect sizes across different measures of social relationships (Holt-Lunstad. 2010).

  People with social relationships defined as adequate are 50% more likely to survive than older adults with social relationships defined as poor or insufficient. The overall effect remains consistent across age (see Figure 2).
  
  It is yet still unclear whether specific types of relationships are more advantageous than others. Giles et al. (2005) showed that the beneficial association between social networks and survival among elderly people may be restricted to relationships with friends and confidants rather than with children and relatives. In a meta-analysis of 53 prospective observational studies on older adults, marriage or support from a partner was found be a significant independent predictor of survival; the overall reduction in mortality risk was 9–15%. However, this association was statistically significant in only half of the studies (Manzoli. 2007).

• As Rizzuto & Fratiglioni (2014) point out, one hypothesis suggests that strong social connec tions can buffer significant stress and protect against ne ative stress-related outcomes:
  

  "People might be protected from adopting stress-related lifestyle choices that are detrimental to health, such as smoking, excessive alcohol consumption and sleep loss." (Rizzuto. 2014)

  The main-effect hypothesis postulates that social support is beneficial regardless of the stress level a person is experiencing; in other words, social support can act protectively even before a stressor is experienced. For instance, persons with social support could be influenced to engage in protective be haviors such as exercise.
  
  Moreover, having a wide range of social ties also provides multiple sources of information that could result in more effective use of available health care and services (Cohen. 2004). No wonder, you have, after all, read only a couple of days ago that education is what protects "poor women from fattening effects of rising wealth" in the SuppVersity Facebook News (read more).
• Stay lean and be avtive, God damnit! There is this unfortunate and die-hard myth of something scientists refer to as the obesity paradox. A term that is misrepresented by overweight journalists and doctors and misunderstood by the ever-increasing number of obese average Joes, for whom the misleading connotations of terms such as "healthy obese" are downright life-threatening. 
  
  And this is not an exaggeration, by the way. If you look at the 30% increase in mortality risk Whitlock et al. (2009) calculated based on a meta-analysis of data from 57 prospective studies that included almost 900,000 adults for every 5-point increase in BMI the attribute "life-threatening" is by no means an exaggeration.

• Although the proportional increase was greater at younger ages (35–59 years), the corresponding increase in mortality for those in their 70s was nearly 30%, and for those in their 80s, it was still 15% - the notion that older people would benefit from being fat is thus simply hilarious.
  
  Whats not hilarious, though, is that a certain amount of healthy, well-distributed body fat thats complemented by a decent amount of life-extending muscle mass (20% reduction in all cause-mortality for men >55years w/ a decent amount of lean mass; see  SuppVersity Facebook News | learn more) and a corresponding BMI between 20-27 offers enough energy reserves to draw on, when youre sick and old. It is thus also not surprising that being slightly overweight (obesity starts with BMI >30) is not a risk factor for people aged ? 65 years (Heiat. 2001) and certainly better than being what scientists call "underweight", when its actually only "undermuscled" for the vast majority of elderly individuals who are affected.

• As a SuppVersity reader you know: The risk for both, being underweight and overweight can be reduced if not nullified by a high amount of daily physical activity (the 10,000 steps mantra) and working out regularly. Being moderately active, alone, for example, was found to be associated with a 3.6x higher chance of "successful [=healthy] aging" in a recent study from the University of Ibadan - for regular vigorous activity, the chance of aging healthily increased by 711% (Gureje. 2014)!

• Miscellaneous, but worth mentioning: This is where I will list everything that popped up on my radar while doing the research, but did not really appear to make a good standalone item in the list. Things like having sex, for example. At least twice a week, to make sure that you dont increase your risk of  fatal coronary heart disease by 180%, guys (Ebrahim. 2002). And ther results Smith et al. presented 5 years before are even more promising: According to their study, each increase of 100 orgasms per year is associated with a 46% reduction in all-cause mortality risk (Smith. 1997)!

It is obviously true that some of the things that determine healthy aging are (still) out of your reach. Most prominently, your sex! Scientists are yet struggling to explain the underlying reasons of the sex-specific "longevity bias", but contemporary research would suggest that...

"[...]female centenarians likely exploited a healthier life-style and more favorable environmental conditions, owing to gender-specific cultural and anthropological characteristics" (Franceschi. 2000) 

... and do thus depend to a lesser extend on having the right mtDNA haplogroups, Thyrosine Hydroxilase, and IL-6 genes than men.

Figure 5: Yes, genes matter, but there is more (Franceschi. 2003)

Apropos genes, the "typically male" aka sex–dependent genetic predisposition to produce high levels of IL?6 is about as detrimental to your goal of making it past the "100+ years finish line" healthily, as being born with the nasty "?4" variety of the apolipoprotein E gene and the corresponding lifelong problems with high blood lipids and an increased risk of cardiovascular disease, Alzheimers & co (Panza. 1999; Bonafè. 2001).

Other genes that have been highlighted as factors that contribute to exceptional longevity are certain variants of the FOXO3A gene (Flachsbart. 2009), ...
References: 

• Berrington de Gonzalez, Amy, et al. "Body-mass index and mortality among 1.46 million white adults." New England Journal of Medicine 363.23 (2010): 2211-2219.
• Bonafè, Massimiliano, et al. "A gender–dependent genetic predisposition to produce high levels of IL?6 is detrimental for longevity." European journal of immunology 31.8 (2001): 2357-2361. 
• Cohen, Sheldon. "Social relationships and health." American psychologist 59.8 (2004): 676.
• Ebrahim, S., et al. "Sexual intercourse and risk of ischaemic stroke and coronary heart disease: the Caerphilly study." Journal of epidemiology and community health 56.2 (2002): 99-102.
• Flachsbart, Friederike, et al. "Association of FOXO3A variation with human longevity confirmed in German centenarians." Proceedings of the National Academy of Sciences 106.8 (2009): 2700-2705.
• Franceschi, C., et al. "Do men and women follow different trajectories to reach extreme longevity?." Aging Clinical and Experimental Research 12.2 (2000): 77-84. 
• Franceschi, C., and M. Bonafe. "Centenarians as a model for healthy aging." Biochemical Society Transactions 31.2 (2003): 457-461. 
• Giles, Lynne C., et al. "Effect of social networks on 10 year survival in very old Australians: the Australian longitudinal study of aging." Journal of Epidemiology and Community Health 59.7 (2005): 574-579. 
• Gureje, Oye, et al. "Profile and Determinants of Successful Aging in the Ibadan Study of Ageing." Journal of the American Geriatrics Society (2014).
• Heiat, Asefeh, Viola Vaccarino, and Harlan M. Krumholz. "An evidence-based assessment of federal guidelines for overweight and obesity as they apply to elderly persons." Archives of internal medicine 161.9 (2001): 1194-1203.
• Holt-Lunstad, Julianne, Timothy B. Smith, and J. Bradley Layton. "Social relationships and mortality risk: a meta-analytic review." PLoS medicine 7.7 (2010): e1000316. 
• Kilpeläinen, Tuomas O., et al. "Physical activity attenuates the influence of FTO variants on obesity risk: a meta-analysis of 218,166 adults and 19,268 children." PLoS medicine 8.11 (2011): e1001116.
• Kloner, Robert A., and Shereif H. Rezkalla. "To drink or not to drink? That is the question." Circulation 116.11 (2007): 1306-1317.
• Larkin, Marilynn. "Centenarians point the way to healthy ageing." The Lancet 353.9158 (1999): 1074.
• Manzoli, Lamberto, et al. "Marital status and mortality in the elderly: a systematic review and meta-analysis." Social science & medicine 64.1 (2007): 77-94. 
• Oliveira, Aldair J., et al. "The influence of social relationships on obesity: sex differences in a longitudinal study." Obesity 21.8 (2013): 1540-1547.
• Panza, Francesco, et al. "Decreased frequency of apolipoprotein E ?4 allele from Northern to Southern Europe in Alzheimers disease patients and centenarians." Neuroscience letters 277.1 (1999): 53-56.
• Perls, Thomas T., Margery Hutter Silver, and John F. Lauerman. Living to 100: Lessons in living to your maximum potential at any age. 1st ed. New York: Basic Books, 1999.
• Rehm, Jürgen, et al. "Alcohol-related morbidity and mortality." Mouth 140.208 (2002): C00-C97. 
• Rizzuto, D., and L. Fratiglioni. "Lifestyle Factors Related to Mortality and Survival: A Mini-Review." Gerontology (2014).
• Rodriguez, Beatriz L., et al. "Fish Intake May Limit the Increase in Risk of Coronary Heart Disease Morbidity and Mortality Among Heavy Smokers The Honolulu Heart Program." Circulation 94.5 (1996): 952-956. 
• Rogers, Richard G., and Eve Powell-Griner. "Life expectancies of cigarette smokers and nonsmokers in the United States." Social science & medicine 32.10 (1991): 1151-1159.
• Sebastiani, Paola, et al. "Genetic signatures of exceptional longevity in humans." Science 10 (2010): 1126. 
• Smith, George Davey, Stephen Frankel, and John Yarnell. "Sex and death: are they related? Findings from the Caerphilly cohort study." Bmj 315.7123 (1997): 1641-1644.
• Stewart, Susan T., David M. Cutler, and Allison B. Rosen. "Forecasting the effects of obesity and smoking on US life expectancy." New England Journal of Medicine 361.23 (2009): 2252-2260.
• Streppel, Martinette T., et al. "Long-term wine consumption is related to cardiovascular mortality and life expectancy independently of moderate alcohol intake: the Zutphen Study." Journal of epidemiology and community health 63.7 (2009): 534-540.

Compared to liquid beverages, gels have the advantage of causing lower GI stress, when significant quantities of CHOs are consumed during exercise. Bars, can be held in the cheek pouch and chewed during critical phases of a race.

The headline gives it away. Todays SuppVersity article is a brief review of the (mostly sponsored) literature on Gatora.... ah, I mean carbohydrate supplementation during exercise. The headline also implies that the usefulness and efficacy of carbohydrate supplements depends on exercise duration and the type of exercise.

As a seasoned student of the SuppVersity you will know that certain paradox involved with regard to the duration / type of exercise. Short exercise durations, for example, shouldnt require large CHO boluses, long duration exercise, on the other hand, is fueled mostly by fat - so why should you supplement with carbohydrates, anyway?
I promise to answer this and other questions in the following paragraphs, but before I do so, I would like to point out that there is as of now no evidence that the much-praised "fat adaptation" increases the exercise performance to an "Olympia" level. Carbohydrate supplements, on the other hand, are still part of the regular supplementation regimen for the 99% of the top athletes.

That being said, the human physiology dictates that the use of carbohydrate supplements during aerobic workouts that last less than 60 minutes is useless, because muscle glycogen is generally not limiting to performance when exercise durations are less than ~60 minutes.

It should not work for short duration exercise, but it still does

Interestingly, 16 out of 23 studies, Trent Stellingwerff and Gregory R. Cox from the Canadian Sport Institute-Pacific and the Australian Institute of Sport reviewed for their recent paper in Applied Physiology have found that carbohydrate supplementation and/or oral (mouth) exposure to carbohydrate can improve performance of tasks less than 1 hour in duration:

You wont fully deplete your muscular glyocogen levels during short duration resistance training (Haff. 2003)

"In 2004 a seminal paper was published showing that a carbohydrate mouth-wash (swirling 25ml of a 6% CHO beverage (only ~1.5g of CHO in 25ml [6.4% maltodextrin solution (CHO)]) around in the mouth for ~10 sec, every 7.5min) significantly improved time trial (TT) performance [in seven male and two female endurance cyclists] by ~3% (Carter et al. 2004a)." (Stellingwerff & Cox. 2014)

This effect of CHO mouth-washing to improve performance in events from 30-60min has now been replicated in several other performance studies (10 of 13 studies) using both cycling and running interventions and with both sweet (sucrose) and non-sweet (maltodextrin) caloric CHO sources,as compared to 5 non-caloric artificial sweetener placebo trials showing no performance enhancing effects.

Figure 1: Hard to believe, but true - In 2010 Pottier et al. observed that CHO mouth-rinsing, but not CHO ingestion increases the 1h high intensity time-trial performance in trained subjects.

 "All these findings have been mechanistically supported with a functional magnetic resonance brain imaging study showing that CHO mouth-washing from both sweet tasting glucose and non-sweet maltodextrin can stimulate the brain areas of the insula/frontal operculum, orbitofrontal cortex and striatum, which are involved with brain centers responsible for reward and motor control (Chambers et al. 2009). Interestingly, if the mouth (oral receptors) and GI tract is by-passed by CHO infusion straight into the blood stream then 1h cycling TT performance was unaltered as compared to no CHO supplementation (Carter et al. 2004b)." (Stellingwerff & Cox. 2014)

Studies evaluating the effects on perceived exertion (Fares et al. 2011) found similar benefits all of which support the idea that the effect does not occur in the musculature, but rather in the head.
It should be obvious that the physiological, or rater intra-muscular benefits of carbohydrate supplements increases with the exercise duration.

CHO supplementation during exercise that lasts 60 minutes or longer

In view of the fact that it is 100% logical and well established by studies by Coyle et al. (Coyle 1992a; Coyle 1992b) that the intake of carbohydrate (glucose alone, and glucose + fructose blends) can significantly improve prolonged endurance capacity and performance (>60min of exercise (Jeukendrup 2010)).

Figure 2: Overview of the performance increases in the 50 studies Stellingwerff & Cox reviewed (2014)

Against that background I will not bother you with another overview of the results, but focus on the efficacy of different carbohydrate supplementation strategies and types of carbohydrate supplements for exercise durations beyond the "magical" hour.

Glucose + fructose - the combination advantage

As a SuppVersity reader youve previously heard about the benefits of combining glucose and fructose in your intra-workout beverage. It is thus only logical that most commercially available formulas are mixtures  glucose + fructose (GLU:FRU) or maltodextrin + fructose - so-called "multi-transportable CHOs". The advantage of using both glucose and fructose is that the carbohydrates will be absorbed via SGLT1 and GLUT5 intestinal transporters.

Specifically during long(er) duration exercise, when the carbohydrate consumption can exceed 60g/h there is a significant performance increase with multi- vs. single source carbohydrate supplements (Stellingwerff & Cox. 2014)

An advantage that has been scientifically established among others by Jeukendrup et al. (2010) who found that this pattern of CHO ingestion results in ~20 to 50% higher CHO oxidation rates compared to the ingestion of a drink that contains nothing but glucose or maltodextrin.


Now an increase in carbohydrate oxidation alone does not sound like something you would aim for as an endurance athlete. In practice, increases in carbohydrate oxidation have yet been shown to increase the performance during prolonged exercise bouts compared to isocaloric glucose-only beverages. (Currell et al. 2008; Triplett et al. 2010; OBrien et al. 2011; OBrien et al. 2013).
Needless to say that there is still research to be done with respect to individual influencing variables of carbohydrate requirements. The currently available evidence, for example, is largely based on results from runners and cyclists. Two other factors / issues that come to mind are...

• the dose-response relationship, which appears to be capped at 75g/h - at least according to a large-scale multi-center study by Smith et al. (Smith. 2013) who found that their subjects, endurance trained cyclists or triathletes experienced significant performance increases, with increasing amounts of carbohydrates (0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110 and 120g of CHO/h) during a 2h constant load ride.
  
  

  Figure 3: Mean log time to complete time trial (natural) as function of CHO treatment condition with fitted quadratic curve (with 95% CI of mean curves). Differences 100 represent percent change in performance. The quadratic function relating CHO ingestion rate to time complete time trial for 43% (95% CI = 11%–75%,P= 0.059) of the variation in mean performance score (Smith. 2013)

  The CHO given was a 1:1:1 glucose:maltodextrin:fructose blend. Results indicated incremental performance improvements of 1.0%, 2.0%, 3.0%, 4.0%, and 4.7% at 9, 19, 31, 48, and 78g CHO/h, respectively, with diminishing performance enhancement seen at CHO levels >78g/h.
  
  The optimal amount for performance (+4.7%) was 78g/h, with a range of 68 to 88g/h. However, even at 10g/h, a 1.0% increase in performance was observed, showing even a small amount of carbohydrate has the potential to positively impact performance. 
• the optimal mix of glucose, dextrose, fructose, maltodextrin or other "special" carbohydrates  - needless to say that waxy maize, hydroxypropyl distarches (learn more) or the expensive fast absorbing highly insulinogenic patented carbohydrate source Vitargo come to mind, when we are talking about finding the optimal mix of different carbohydrate sources - a mix, by the way, of which you can safely assume that it will differ according to the physiological demands of the workout and the exercise duration.
  
  One thing we shouldnt forget, though, is that next to optimal performance, optimal GI tolerance, i.e. the absence of bloating, diarrhea & co would be an important criteria the "optimal" carbohydrate blend would have to meet.

• Figure 4: CHO suppl. ameliorates  testosterone reductions in 800m runners (de Sousa. 2010)

  the impact of carbohydrate supplementation on hormonal changes during and in response exercise - several human studies suggest that CHO supplementation attenuates the suppression of the hypothalamic-pituitary-gonadal axis and the rise in stress hormones during periods of intense training; a recent rodent study shows that the provision of carbohydrate supple- ments can prevent / reverse exercise-associated menstrual dysfunction (de Sousa. 2010; Zhao. 2014)

I guess, I could come up with additional research gabs, but in the end, a list of "gaps" is not exactly useful for you. Much in contrast to a conclusion, which I am about to formulate in the bottom line, now.
References:

• Carter,  J.,  Jeukendrup,  A.E.,  Mundel,  T.,  and  Jones,  D.A.  (2003).  Carbohydrate  supplementation  improves moderate and high-intensity exercise in the heat. Pflügers Archiv : European journal of physiology446: 211-9.
• Carter, J.M., Jeukendrup, A.E., and Jones, D.A. (2004a). The effect of carbohydrate mouth rinse on 1-h cycle time trial performance. Medicine and science in sports and exercise36: 2107-11.
• Carter, J.M., Jeukendrup, A.E.,  Mann, C.H., and  Jones, D.A. (2004b). The effect of glucose infusion on glucose kinetics during a 1-h time trial. Medicine and science in sports and exercise36: 1543-50. 
• Chambers,  E.S.,  Bridge,  M.W.,  and  Jones,  D.A.  (2009). Carbohydrate  sensing  in  the  human  mouth:  effects  on exercise performance and brain activity. The Journal of physiology587: 1779-94. 
• de Sousa, Maysa Vieira, et al. (2010). Effects of carbohydrate supplementation on competitive runners undergoing overload training followed by a session of intermittent exercise." European journal of applied physiology 109.3: 507-516.
• Fares, E.J. and Kayser, B. (2011). Carbohydrate mouthrinse effects on exercise capacity in pre- and postprandial States. J Nutr Metab2011: 385962.   
• Pottier, Andries, et al. (2010). Mouth rinse but not ingestion of a carbohydrate solution improves 1?h cycle time trial performance" Scandinavian journal of medicine & science in sports 20.1: 105-111.
• Sawka,  M.N.,  Burke,  L.M.,  Eichner,  E.R.,  Maughan,  R.J.,  Montain,  S.J.,  and  Stachenfeld,  N.S. (2007).  American College of Sports Medicine position stand. Exerciseand fluid replacement. Medicine and science in sports and exercise39: 377-90.
• Smith, JohnEric W., et al. (2013). Curvilinear dose-response relationship of carbohydrate (0-120 g/h) and performance." Med Sci Sports Exerc 45.2: 336-341. 
• Stellingwerff, T., & Cox, G. R. (2014). Systematic Review: Carbohydrate Supplementation on Exercise Performance or Capacity of Varying Durations. Applied Physiology, Nutrition, and Metabolism (2014). Ahead of Print. 
• Zhao, Can, et al. (2014). Effects of carbohydrate supplements on exercise-induced menstrual dysfunction and ovarian subcellular structural changes in rats." Journal of Sport and Health Science 3.3: 189-195.