Greater Daily Intake Research Articles

Nutritional strategies in an elite wheelchair marathoner at 3900\u2009m altitude: a case report

BackgroundAltitude training is a common practice among middle-distance and marathon runners. During acclimatization, sympathetic drive may increase resting metabolic rate (RMR), therefore implementation of targeted nutritional interventions based on training demands and environmental conditions becomes paramount. This single case study represents the first nutritional intervention performed under hypobaric hypoxic conditions (3900 m) in Paralympic sport. These results may elucidate the unique nutritional requirements of upper body endurance athletes training at altitude.Case presentationThis case study examined the effects of a nutritional intervention on the body mass of a 36-year-old professional wheelchair athlete (silver medalist at the Paralympic Games and 106 victories in assorted road events) during a five-week altitude training camp, divided into pre-altitude at sea level (BN), acclimatization to altitude (Puno, 3860 m) (BH), specific training (W1,2,3,4) and return to sea level (Post) phases. Energy intake (kcal) and body mass (kg) were recorded daily. Results demonstrated significant decrease in body mass between BN and BH (52.6 ± 0.4 vs 50.7 ± 0.5 kg, P < 0.001) which returned to pre-altitude values, upon returning to sea level at Post (52.1 ± 0.5 kg). A greater daily intake was observed during BH (2899 ± 670 kcal) and W1,2,3 (3037 ± 490; 3116 ± 170; 3101 ± 385 kcal) compared to BN (2397 ± 242 kcal, P < 0.01) and Post (2411 ± 137 kcal, P < 0.01). No differences were reported between W4 (2786 ± 375 kcal), BN and Post. The amount of carbohydrates ingested (g · kg− 1) was greater in W1,2,3, (9.6 ± 2.1; 9.9 ± 1.2; 9.6 ± 1.2) than in BN (7.1 ± 1.2) and Post (6.3 ± 0.8, P < 0.001). Effect sizes (Cohen’s d) for all variables relative to BN (all time points) exceed a large effect (d > 0.80).ConclusionsThese results suggest an elite wheelchair marathoner training at 3860 m required increased nutrient requirements as well as the systematic control needed to re-adapt a nutritional program. Moreover, our findings highlight training and nutritional prescription optimization of elite wheelchair athletes, under challenging environmental conditions.

Prediction of porcine carcass iodine value based on diet composition and fatty acid intake.

The pig industry uses a variety of fat sources (FS) and fat levels (FL) in diets to increase energy content. The objective was to investigate the impact of FS and FL on rate and efficiency of gain, apparent total tract digestibility of dietary fat, and pork fat composition and test dietary predictors of carcass iodine value (IV). A total of 1,213 pigs (PIC 280 × PIC Camborough 42; PIC, Inc., Hendersonville, TN) with an initial BW of 32.0 ± 0.4 kg were randomly allotted to 1 of 6 dietary treatments on d 0. Treatments were arranged as a 2 × 3 factorial, with 2 FS, choice white grease (CWG; IV = 66.8) and corn oil (COIL; IV = 123.2), and 3 FL, 2, 4, or 6%. Ten pens of approximately 20 pigs each (0.70 m/pig) were randomly assigned to each of the 6 treatments. All pigs were on trial for 105 d. Pigs were harvested in 1 of 3 marketing pulls, to achieve an ideal market BW across differing rates of gain, at which time belly fat samples were collected (d 105 [457 pigs], 117 [309 pigs], or 134 [432 pigs]). Diet and belly fat samples were analyzed for fatty acid profile. Daily rate of gain was not impacted by FS or FL ( ≤ 0.325). Increasing FL and dietary energy concentration increased G:F ( < 0.001). No difference was evident for G:F between FS ( = 0.107). Increasing FL of CWG resulted in greater daily intake of SFA and MUFA than increasing FL of COIL ( < 0.001). Increasing levels of COIL resulted in greater daily intake of PUFA than increasing levels of CWG ( ≤ 0.012). Feeding CWG tended to result in great caloric efficiency adjusted for carcass yield than feeding COIL ( = 0.074). The inclusion of COIL instead of CWG tended to increase true total tract digestion of acid hydrolyzed ether extract on d 39 ( = 0.066) but not on d 104 ( = 0.402). Increasing COIL increased carcass IV at a greater magnitude than increasing CWG, resulting in a FS × FL interaction on d 105, 117, and 134 ( < 0.001). Dietary linoleic acid concentration and daily intake had a stronger linear relationship than IV product (IVP; = 0.95 vs. = 0.94 vs. = 0.85, respectively). In conclusion, limiting linoleic acid dietary concentration and intake is key to lowering carcass IV. To meet a carcass IV standard of 74 g/100 g, linoleic acid concentration had to be <3.4% and intake had to be <88 g/d. Dietary linoleic acid is a superior predictor of carcass IV compared with IVP, especially when high-fat diets are used.

Genotoxic Impurities: A Quantitative Approach

Starting materials, intermediates and by-products are often found as impurities in active pharmaceutical ingredients (APIs). Some of these known impurities are potential mutagens or carcinogens but can be difficult or impossible to eliminate completely from the synthetic scheme. Based on current regulatory guidances for genotoxic impurities, analytical methods should be developed to meet the required limit of 1.5 µg/day daily intake of each individual impurity for new drug substances. During the early clinical development stages the Pharma Task group proposed a staged TTC concept, where greater daily intake can be allowed. The allowable daily intake thus calculated would then provide a basis for estimating the quantitation limit (QL) required for the development of an analytical method for determining genotoxic impurity levels. The approach for choosing an analytical technique will depend on many factors including availability of the instrumentation and physical and chemical properties of the analyte. Although UV absorbance is normally the first choice detection technique for HPLC analysis, many genotoxic impurities lack a UV chromophore and consequently are not suitable for quantitation via UV detection. The examples described in this report show different approaches for quantitation on a case-by-case basis using various detection techniques such as UV, ELSD, CAD and MS. Although in one case the required alert level of 30 ppm was easily achieved using standard UV detection, other examples highlight the need for using alternatives such as an LC-MS/MS method. The latter methodology was necessary to achieve a required QL level of 57 ppm for one particular impurity. Validation of this method as per ICH guidelines with respect to specificity, linearity, accuracy and QL is also discussed.