Sex differences in postprandial lipaemia after acute high-intensity interval running in young people

Abstract

Acute exercise reduces postprandial triacylglycerol concentrations ([TAG]) in boys and girls; however, it is not known whether between-sex differences exist in response to exercise. Fifteen boys (mean(SD): 11.8(0.4) years) and sixteen girls (12.1(0.7) years) completed two, 2-day conditions. On day 1, participants rested (CON) or completed 10 × 1 min high-intensity interval runs at 100% maximal aerobic speed with 1 min recovery (HIIR). On day 2, participants consumed a standardised breakfast and lunch over a 6.5-h period during which seven capillary blood samples were collected. Based on ratios of the geometric means (95% CI for ratios), fasting [TAG] was 32% lower in boys than girls (-44 to -18%, ES = 1.31, P < 0.001), and 12% lower after HIIR than CON (-18 to -5%, ES = 0.42, P = 0.003); the magnitude of reduction was not significantly different between the sexes (8% (ES = 0.36) vs. 15% (ES = 0.47), respectively; P = 0.29). The total area under the [TAG] versus time curve was 27% lower in boys than girls (-40 to -10%, ES = 1.02, P = 0.005), and 10% lower after HIIR than CON (-16 to -5%, ES = 0.36, P = 0.001); the magnitude of reduction was similar between the sexes (11% (ES = 0.43) vs. 10% (ES = 0.31), respectively; P = 0.87). The small-moderate reduction in postprandial [TAG] after HIIR was similar between the sexes.

Exercise to Lower Postprandial Lipemia: Why, When, What and How

“…Since 2014, 36 studies have confirmed that exercise performed on the evening prior to a morning high-fat meal (that is, a meal containing above 0.7 g of fat per kg body mass) lowers PPL, compared to no exercise. This has been shown in young, middle-aged and/or older men [14, 21-23, 27-43, 76, 77], young men and women [44], young or middle-aged women [45,67], normal and overweight individuals [68], overweight and obese individuals [24,46,47] and adolescent boys and girls [48][49][50][51][52][53].…”

“…On the contrary, all studies using submaximal, high-volume interval exercise showed reductions in PPL [11]. Studies published afterwards showed that HIIE in the form of running or cycling reduced PPL when performed on i. the day before a high-fat meal [22,23,37,47,48,51,52],…”

“…TAG reduction of 22% (range 4 to 35%) [14,28,[37][38][39][40][41][42][43][44][45][46]29,[47][48][49][50][51][52][53][54][55][56]30,[57][58][59][60][61][62][63][64][65][66]31,67,68,[32][33][34][35][36]. iv.…”

“…To document this, we examined how many of the original studies that are included in the present review and showed a significant effect of exercise on PPL satisfied the criterion of lowering circulating TAG by at least 1 mmo/L, which is the minimal established clinically relevant effect 15 16 . On this basis, 7 studies demonstrated a clinically relevant effect, with an average TAG reduction of 38% (range 29 to 47%) 21 22 23 24 25 26 27 , whereas 42 studies did not find a clinically relevant effect, with an average TAG reduction of 22% (range 4 to 35%) 14 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 .…”