A comparison of diet quality and cardiovascular and inflammatory responses between aerobically trained male adults following either a long-term vegan or omnivorous dietary pattern

Vegan dietary patterns are increasingly being adopted by endurance athletes, yet research examining the influence of this dietary pattern on exercise-related physiology is limited. This pilot study, therefore, aimed to explore nutrient status, diet quality and cardiovascular and inflammatory responses in aerobically trained adult males following vegan and omnivorous dietary patterns during aerobic exercise. An incremental ramp running test was used to assess peak oxygen consumption (VO_2peak ) in males aged 18-55 years, engaging in >4 h training/week. Exercise testing was performed during walking and steady-state running conditions (60% and 90% of VO_2peak ). Participants were grouped by dietary pattern type and were equivalent for age, training volume and VO_2peak . When compared to the omnivorous group (n = 8, age 35.6 years, VO_2peak 55.7 mL/kg/min), the vegan group (n = 12, age 33.4 years, VO_2peak 56.4 m/kg/min) consumed more energy from carbohydrates (p = 0.007), and less energy from protein (p = 0.001) while exhibiting a higher overall diet quality score (p = 0.008). No differences in inflammatory biomarkers were observed before or after running. Total red blood cell count, haemoglobin and haematocrit levels were lower in the vegan dietary group. In summary, aerobically trained males, following a long-term vegan diet, can tolerate a short bout of running broadly comparatively to their omnivore counterparts. More arduous endurance exercise conditions should be explored to further uncover potential outcomes of consuming a vegan dietary pattern and exercise-related physiology.