This randomized, double-blind pilot study evaluated how repeated intake of gummies containing the slow-digesting disaccharide isomaltulose versus sucrose affected physiological stress markers, glycemic dynamics, subjective states, and performance during a competitive 18-hole golf round. The investigation targeted prolonged, moderate-intensity exercise where sustained physiological stability is important for performance and recovery.
Twenty-three male collegiate golfers were randomized to one of two groups: the isomaltulose group (ISO; n = 12) or the sucrose control group (CON; n = 11). The trial used a double-blind controlled design. After completing each hole, participants consumed a gummy that contained 12.1 g of carbohydrate per hole, yielding a reported total carbohydrate intake of 217.5 g over the full 18-hole round.
Affiliations and investigator details were provided in the source; the trial was published in the Journal of the International Society of Sports Nutrition.
Primary outcomes were salivary markers of physiological stress: dehydroepiandrosterone sulfate (DHEAS), testosterone, and cortisol. Secondary outcomes included interstitial glucose concentration measured with continuous glucose monitoring (CGM), subjective assessments (sleepiness, relaxation, concentration), and objective golf performance measured by 18-hole score. Between-group comparisons at each time point used planned Welch’s t-tests as reported.
Exploratory analyses identified differential hormonal trajectories between groups. During the latter half of the round, saliva concentrations of DHEAS and testosterone were higher in the ISO group compared with the CON group (reported p < 0.05). In contrast, both DHEAS and testosterone showed declines in the CON group over the course of play. The abstract does not report detailed time-series hormone values, baseline equivalence testing, or cortisol results beyond stating that salivary stress markers were primary outcomes; specific cortisol findings were not detailed in the abstract.
Mean interstitial glucose concentration measured by CGM did not differ significantly between groups (p = 0.20). Glycemic variability showed a trend favoring the ISO group: standard deviation of interstitial glucose was reported as ISO 14.7 ± 1.9 mg/dL versus CON 16.7 ± 4.6 mg/dL, with a medium effect size (d = 0.58). The study notes this difference was not statistically significant.
Subjective outcomes diverged between groups. The sucrose (CON) group reported significantly greater subjective arousal—specifically measures of wakefulness and relaxation—compared with ISO (p < 0.01). The abstract does not present full scales, timing of subjective assessments, or absolute values for those measures.
Objective golf performance, measured as 18-hole score, did not differ between groups (p = 0.38).
The authors frame many of the hormonal and glycemic observations as exploratory. The abstract does not provide detailed repeated-measures statistical models, confidence intervals for reported effect sizes, or exact time-point data tables.
Interpretation The data suggest that continuous intake of an isomaltulose-containing gummy across an 18-hole golf round was associated with higher late-round salivary DHEAS and testosterone and a non-significant trend toward lower glycemic variability compared with sucrose. These physiological differences were not accompanied by improved objective golf performance in this cohort.
Limitations reported or apparent from the abstract
Implications for practice While isomaltulose may moderate glycemic dynamics and some salivary hormones during prolonged moderate-intensity play, current evidence from this pilot does not support a clear performance benefit in golf when compared with sucrose. Practitioners and athletes should interpret these preliminary physiological signals cautiously until larger, adequately powered trials clarify clinical and performance relevance.
Continuous intake of isomaltulose-containing gummies during an 18-hole round was associated with differences in selected physiological markers—specifically salivary DHEAS and testosterone—and a tendency toward reduced glycemic variability, without improvement in 18-hole score compared with sucrose-containing gummies. The authors conclude that these findings are exploratory. They recommend larger-scale studies with appropriate repeated-measures designs to determine whether the observed hormonal and glycemic changes translate into meaningful performance, fatigue mitigation, or recovery advantages.
Note: the abstract provides p values, group sizes, carbohydrate dosing, and select summary statistics; additional methodological and detailed results information were not reported in the abstract and would require review of the full article for complete appraisal.