Ageing is associated with reduced appetite and energy intakes. However, the mechanisms underlying this phenomenon are not fully understood. This systematic review and meta-analysis quantified differences in circulating concentrations of appetite-related hormones between healthy older and younger adults. Six databases were searched through 12th June 2018 for studies that compared appetite-related hormone concentrations between older and younger adults. Data were pooled using random-effects meta-analysis and are presented as standardised mean difference (Hedges’ g) with 95% confidence intervals (95% CI). Thirty-five studies were included involving 710 older adults (mean ± SD; age: 73 ± 5 years) and 713 younger adults (age: 28 ± 7 years). Compared with younger adults, older adults exhibited higher fasted and postprandial concentrations of the anorectic hormones cholecystokinin (Fasted: SMD 0.41 (95% CI 0.24, 0.57); p < 0.001. Postprandial: SMD 0.41 (0.20, 0.62); p < 0.001), leptin [Fasted: SMD 1.23 (0.15, 2.30); p = 0.025. Postprandial: SMD 0.62 (0.23, 1.01); p = 0.002] and insulin [Fasted: SMD 0.24 (− 0.02, 0.50); p = 0.073. Postprandial: SMD 0.16 (0.01, 0.32); p = 0.043]. Higher postprandial concentrations of peptide-YY were also observed in older adults compared with younger adults [SMD 0.31 (− 0.03, 0.65); p = 0.075]. Compared with younger adults, older adults had lower energy intakes [SMD − 0.98 (− 1.74, − 0.22); p = 0.011], and lower hunger perceptions in the fasted [SMD − 1.00 (− 1.54, − 0.46); p < 0.001] and postprandial states [SMD − 0.31, (− 0.64, 0.02); p = 0.064]. Higher circulating concentrations of insulin, leptin, cholecystokinin and peptide-YY accord with reduced appetite and energy intakes in healthy older adults. Interventions to reduce circulating levels of these hormones may be beneficial for combatting the anorexia of ageing.

Cross-sectional studies in younger adults have demonstrated a positive association between energy intake (EI) and fat-free mass (FFM), with this relationship seemingly mediated by resting metabolic rate (RMR). Establishing a causal effect longitudinally would be prudent in older adults suffering from loss of appetite. We investigated the effects of FFM on RMR, appetite and EI in 39 healthy older adults (age: 66 ± 4 years, BMI: 25.1 ± 3.5 kg∙m²) assigned to either 12-week resistance training + protein supplementation group (RT + PRO) or control group (CON). Body composition, subjective appetite, leptin, insulin, RMR and laboratory-measured ad libitum EI were measured at baseline, weeks 6 and 12 of the intervention, while daily EI at baseline and week 12. FFM (+1.2 kg; p = 0.002), postprandial subjective appetite (+8 mm; p = 0.027), ad libitum EI (+119 kcal; p = 0.012) and daily EI (+133 kcal; p = 0.010) increased from baseline to week 12 in the RT + PRO. RMR, fasted subjective appetite, leptin and insulin concentrations remained unchanged (all p > 0.05). The increases ad libitum EI correlated with increases in FFM (r = 0.527, p = 0.001), with 54% of the change in EI attributed to FFM changes. In conclusion, FFM increases were associated with an increased ad libitum EI and postprandial appetite in older adults.

We used stable isotope methodology to evaluate exogenous rates of CHO oxidation in elite male marathoners. We report that 120 (maltodextrin:fructose ratio 1:1) g·h ⁻¹ CHO induces greater whole body and exogenous CHO oxidation compared with 60 (1:0)–90 (2:1) g·h ⁻¹ and reduces the O ₂ cost of running. However, the performance implications of such doses remain to be determined. The prevalence of GI symptoms across the doses suggests targeted fueling practice and gut training is warranted.

This study examined the effects of graded carbohydrate (CHO) ingestion at rates of 0 (water only), 60 and 120 g·h ⁻¹ (1:0.8 ratio of maltodextrin‐to‐fructose) on changes in critical power following 3‐h of moderate‐intensity cycling in endurance‐trained cyclists/triathletes ( n = 16; V̇O _2max 51.8 ± 6.8 mL·kg ⁻¹ ·min ⁻¹ ). Following a standardized 24‐h CHO loading protocol (8 g·kg ⁻¹ ) and pre‐exercise meal (2 g·kg ⁻¹ ), participants completed a 3‐min critical power (CP) test, with end‐test power (EP) and work done above EP used as estimates of CP and W ′ , respectively, in a non‐fatigued state and after 3‐h of cycling at 95% gas exchange threshold (‘fatigued’ state). CP was significantly reduced ( p < 0.001) after the 3‐h exercise in all experimental conditions (water: 236 ± 30 W; 60 g·h ⁻¹ : 257 ± 28 W; 120 g·h ⁻¹ : 266 ± 29 W) compared to the non‐fatigued state (277 ± 27 W). However, this reduction in CP was attenuated with increasing CHO intake during exercise in a dose‐dependent manner, such that CP after 3‐h was greater in the 120 g·h ⁻¹ vs. 60 g·h ⁻¹ vs. water condition ( p < 0.05). W ′ declined over time, with no differences between fatigued conditions ( p > 0.05). Mean whole‐body CHO oxidation rates were significantly higher ( p < 0.001) with increasing CHO intake (water: 1.84 ± 0.28; 60 g·h ⁻¹ : 2.16 ± 0.15; 120 g·h ⁻¹ : 2.31 ± 0.14 g·min ⁻¹ ). These data suggest that CHO ingestion at 120 g·h ⁻¹ limits the reduction in CP following prolonged moderate‐intensity cycling, with no effect on W ′ . These findings demonstrate that the boundary between heavy‐ and severe‐intensity exercise shifts under fatigue, with CHO availability possibly acting as a key modulator of endurance durability.

Background/Objectives: Despite increasing awareness of best sports nutrition practices, discrepancies persist between knowledge and behaviour amongst female endurance athletes. Methods: To understand this discrepancy study investigated dietary practices, macronutrient intakes, and influ-encing factors using a multi-method approach. Seventy-two female endurance athletes (42 ± 9 y) completed four-day weighed food diaries, and a subset of twenty athletes (40 ± 10 y) then participated in semi-structured interviews. Quantitative analysis revealed that athletes met the lower end of carbohydrate (CHO) guidelines on rest days (3.0 g·kg⁻¹), but intake fell short on training days, with deficits increasing as training volume rose (moderate: −1.4 g·kg⁻¹, high: −3.5 g·kg⁻¹, very high: −5.5 g·kg⁻¹). Despite awareness of CHO’s role in performance, athletes unintentionally underfuelled, leading to a cumu-lative energy deficit. Energy intake increased by 473 kcal·day⁻¹ per 1000 kcal·day⁻¹ of exercise energy expenditure. In contrast, protein intake was prioritised, with mean in-takes of 1.7 ± 0.7 g·kg⁻¹·day⁻¹ aligning with recommendations. Results: Qualitative findings iden-tified barriers to CHO intake, including time constraints, diet culture influences and body image concerns. Social and environmental factors, such as household environments and professional nutrition guidance, played a critical role in behaviours. Conclusions: These findings highlight the need for practical, evidence-based nutrition interventions to support fe-male endurance athletes. Personalised education addressing CHO requirements, the psychology/emotions around nutrition, and the influence of social environments may bridge the gap between knowledge and practice, optimising both performance and long-term health outcomes.