Age-related impairments in the regulation of food intake. Habitual physical activity differentially affects acute and short-term energy intake regulation in young and older adults Exercise and training effects on gastric emptying of carbohydrate beverages. Exercise training and nutritional supplementation for physical frailty in very elderly people.
Low food intake in elderly individuals increases the risk for many nutrition-related acute or chronic illnesses . It is not known whether aging is associated with changes in hunger and satiety , or whether elderly individuals can regulate energy intake in response to manipulations of the energy or nutrient content of foods . Therefore , this study investigated short-term energy regulation in healthy elderly ( n = 16 ; aged 60 - 84 y ) and young ( n = 16 ; aged 18 - 35 y ) men . Participants were given yogurt preloads that varied in energy and macronutrient content ( low-fat , low-energy , 962 kJ ; high-fat , high-energy , 2134 kJ ; high-carbohydrate , high-energy 2134 kJ ) , or no yogurt , followed by a self-selected lunch ( presented 30 min after subjects began to consume the yogurt ) . Energy intake , the percentage of macronutrients consumed in the meals , and subjective sensations of hunger and satiety were analyzed . The elderly men consumed significantly less energy than the young men in the baseline ( no yogurt ) condition . Lower intake was concordant with subjective sensations of satiety ; visual analog data indicated that the older men were less hungry and more full at the start of lunch . Compensation for energy in the preloads was less precise in the elderly than in the young men , in that elderly men consistently overate at the self-selected lunch . Young men consumed + /- 10 % total energy ( lunch + yogurt ) in the yogurt preload conditions compared with their baseline intake ; elderly men overate between 10 % and 30 % in relation to their baseline intake . ( ABSTRACT TRUNCATED AT 250 WORDS Background : Energy intake ( EI ) regulation is impaired in older adults , but it is not known if habitual physical activity affects accuracy of EI regulation in older compared with young adults . Objective : We hypothesized that the ability to compensate for a high-energy yogurt preload beverage at a subsequent ad libitum meal ( i.e. acute compensation ) and over the course of the testing day ( i.e. short-term compensation ) would decrease with age , but the magnitude of the decline would be smaller in physically active compared with sedentary older adults . Design : On two occasions , young active ( n=15 ) , young sedentary ( n=14 ) , older active ( n=14 ) and older sedentary ( n=11 ) subjects consumed either a high-energy yogurt preload beverage ( YP : 500 ml , 1988 kJ , men ; 375 ml , 1507 kJ , women ) , or no preload ( NP ) , 30 min before an ad libitum test meal . EI at both ad libitum meals was measured , and total daily EI was determined on both testing days . Percent EI compensation for the YP was calculated for the test meal and testing day to determine acute and short-term compensation . Results : Percent EI compensation at the test meal was significantly lower in the older compared with the young subjects ( 65±4 vs 81±4 % , P=0.005 ) . There was no effect of habitual physical activity level on acute compensation , and no age by physical activity level interaction ( P=0.60 ) . In contrast , short-term compensation was not different with age ( 87±5 vs 93±6 % , older vs young , P=0.45 ) , but was more accurate in active vs sedentary subjects ( 100±5 vs 79±6 % , P=0.01 ) . As with acute compensation , there was no age by physical activity interaction ( P=0.39 ) . Conclusion : Acute EI regulation is impaired in older adults , which is not attenuated by physical activity status . However , EI regulation over the course of a day is more accurate in active vs sedentary adults , which may facilitate long-term energy balance . Future work is needed to determine if higher energy expenditure in older active vs older sedentary adults improves long-term EI regulation Carbohydrate containing drinks are commonly consumed as an ergogenic aid during endurance sports activities . The efficacy of a given drink is limited by the rate of absorption , which is in turn limited by gastric emptying . A myriad of factors influence gastric emptying . The influence of several of these factors ( training status , exercise intensity , and carbohydrate composition ) was investigated by repeated experiments using a nasogastric tube and a modification of the technique of George .  A group of well-trained bicyclists and a group of untrained subjects performed similar experiments . Three different carbohydrate containing drinks ( 15 g.100 ml-1 glucose ( G ) , 15 g.100 ml-1 maltodextrin plus 3 g.100 ml-1 fructose ( MD ) , 7 g.100 ml-1 sucrose ( I ] and artificially sweetened water were compared during rest and 50 and 70 % Wmax bicycling . Experimental design was crossover . There was a trend for the carbohydrate drinks to empty initially more slowly under the influence of exercise . Differences in drink volume remaining in the stomach were significant ( P less than 0.05 ) , with I at 10 min ( 70 % , mean = 48.9 % ; rest , mean = 30.5 % ) and at 20 min ( 70 % , mean = 28.9 % ; rest , mean = 23.8 % ) and with MD at 10 min ( 70 % , mean = 71.1 % ; rest , mean = 55.9 % ) . A similar trend was also seen with 50 % Wmax exercise ; however , this trend was only significant with MD at 10 min ( 50 % , mean = 72.1 % ; rest , mean = 55.9 % ) . Drink composition was a much stronger inhibitor of gastric emptying . However , all drinks emptied exponentially with fast-phase initial emptying rates . No differences in gastric emptying or secretion were observed between trained and untrained subjects BACKGROUND Although disuse of skeletal muscle and undernutrition are often cited as potentially reversible causes of frailty in elderly people , the efficacy of interventions targeted specifically at these deficits has not been carefully studied . METHODS We conducted a r and omized , placebo-controlled trial comparing progressive resistance exercise training , multinutrient supplementation , both interventions , and neither in 100 frail nursing home residents over a 10-week period . RESULTS The mean ( + /- SE ) age of the 63 women and 37 men enrolled in the study was 87.1 + /- 0.6 years ( range , 72 to 98 ) ; 94 percent of the subjects completed the study .  Muscle strength increased by 113 + /- 8 percent in the subjects who underwent exercise training , as compared with 3 + /- 9 percent in the nonexercising subjects ( P < 0.001 ) . Gait velocity increased by 11.8 + /- 3.8 percent in the exercisers but declined by 1.0 + /- 3.8 percent in the nonexercisers ( P = 0.02 ) . Stair-climbing power also improved in the exercisers as compared with the nonexercisers ( by 28.4 + /- 6.6 percent vs. 3.6 + /- 6.7 percent , P = 0.01 ) , as did the level of spontaneous physical activity . Cross-sectional thigh-muscle area increased by 2.7 + /- 1.8 percent in the exercisers but declined by 1.8 + /- 2.0 percent in the nonexercisers ( P = 0.11 ) . The nutritional supplement had no effect on any primary outcome measure . Total energy intake was significantly increased only in the exercising subjects who also received nutritional supplementation . CONCLUSIONS High-intensity resistance exercise training is a feasible and effective means of counteracting muscle weakness and physical frailty in very elderly people . In contrast , multi-nutrient supplementation without concomitant exercise does not reduce muscle weakness or physical frailty
Ageing often causes a reduction in appetite and energy intake in older adults which can result in malnutrition .
Current guidelines for older adults suggest increasing physical activity to enhance appetite .
However , it is unclear if there is evidence to support this advice .
This aim of this review is to assess if appetite and energy intake is changed in older adults that undertake acute or regular physical activity  ( measured from cross sectional and intervention studies ) .