Table 1.
Characteristics of studies included in the meta-analysis
| Authors | Title of study | PSE dose (mg) | Time of ingestion pre exercise (min) | Washout period (days) | VO2 max (ml/kg/min) | No. of participants | Sex (mean age ± SD) | Type of exercise | Dominant energy source for exercise | Parameters measured (included in meta-analysis) | Subgroup for analysis | Conclusion of study |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Bright et al. [6] | “Selected cardiac and metabolic responses to pseudoephedrine with exercise” | 60 or 120 | 60 | 7 | / | 6 | Male (25.5) |
Approx. 12 min multistage treadmill running exercise until 85% max. HR was reached | Aerobic | blood glucose | LD, SE, YA, LW, SI, RU | No significant changes in cardiovascular or metabolic parameters. |
| Clemons and Crosby [8] | “Cardiopulmonary and subjective effects of a 60 mg dose of pseudoephedrine on graded treadmill exercise” | 60 | 70 | 7 | 58.46 | 10 | Female (20.4 ± 1.71) | Seven 3 min continuous running exercise stages with speed increasing at 19.22 m/min in each stage | Aerobic | HR, RPE | LD, SE, YA, VL, LW, SI, RU | No effect although it may augment submaximal exercise HR and slow HR recovery. |
| Gillies et al. [9] | “Pseudoephedrine is without ergogenic effect during prolonged exercise” | 120 | 120 | 7 | / | 10 | Male (23.3 ± 2.84) | Approx. 60 min high-intensity exercise (40 km cycling time trial) | Aerobic | TT | LD, LE, YA, LW, LI, CY | No ergogenic effect during prolonged exercise. |
| Swain et al. [12] | “Do pseudoephedrine or phenylpropanolamine improve maximum oxygen uptake and time to exhaustion?” | 1 mg/kg or 2 mg/kg (78.62 mg or 157.24 mg) | 60 | 7 | 59.52 | 20 | Male (27.1 ± 3.73) | 10 s to achieve 80 rpm in a cycling trial with test ending when subjects are unable to maintain speed after 10s | Aerobic | RPE | LD, SE, YA, VL, LW, SI, CY | No ergogenic effect. |
| Gill et al. [13] | “Muscular and cardiorespiratory effects of pseudoephedrine in human athletes” | 180 | 45 | 7 | / | 22 | Male (21.0 ± 2.8) | Maximal (30 s “all-out”) cycle sprint (cycling) | Anaerobic | HR, blood lactate | HD, SE, YA, LW, SI, CY | Improved peak power during maximal cycle performance. |
| Chester et al. [7] | “Physiological, subjective and performance effects of pseudoephedrine and phenylpropanolamine during endurance running exercise” | 60 (6 doses over 36 h) | 240 | 7 | 65.46 | 8 | Male (29.58 ± 8.42) | 20 min running followed by a 5000-m time trial | Aerobic | HR, blood lactate, blood glucose | HD, LE, OA, VH, LW, LI, RU | No ergogenic effect with regard to endurance running. |
| Hodges, et al. [11] | “Effects of pseudoephedrine on maximal cycling power and submaximal cycling efficiency” | 60 | 90 | 3 | 56.8 | 11 | Male (29.0 ± 8.6) | 10 min cycling test (at 40% and 60% of peak power) and 30 s maximal cycle test | Aerobic and Anaerobic | HR | LD, SE, OA, VL, SW, LI, CY | No effect on anaerobic cycling performance or aerobic cycling efficiency. |
| Hodges, et al. [14] | “Pseudoephedrine enhances performance in 1500-m runners” | 2.5 mg/kg (170 mg) | 90 | 7 | 68.7 | 7 (1 dropout) | Male (20.1 ± 1.2) | 1500-m running exercise | Aerobic | HR, blood lactate, blood glucose, TT | LD, SE, YA, VH, LW, LI, RU | Improvement (by 2.1%) in 1500-m running performance |
| Mouatt [23] | “The physiological effects of pseudoephedrine on endurance cycling” | 2.5 mg/kg (184 mg) | 90 | 6 | 66.1 | 10 | Male (29.7 ± 7) | 120 min cycling exercise at fixed intensity and 30 min self-paced time trial | Aerobic | HR, blood glucose, TT, RPE | HD, LE, OA, VH, SW, LI, CY | Increased heart rate but unchanged cycling performance during endurance cycling. |
| Betteridge et al. [20] | “The effect of pseudoephedrine on self-paced endurance cycling performance” | 2.5 mg/kg (187.5 mg) | 90 | 6 | 69 | 8 | Male (29.0 ± 6) | 150 min cycling exercise at 70% VO2 max | Aerobic | HR, TT | HD, LE, OA, VH, SW, LI, CY | No effect on self-paced endurance exercise performance but may affect the cardiac response to exercise. |
| Pritchard-Peschek et al. [15] | “Pseudoephedrine ingestion and cycling time-trial performance” | 180 | 60 | 3.5 | 56.8 | 6 | Male (33 ± 2) | Approx. 30 min cycling exercise at 7 kJ/kg BM workload | Aerobic | HR, blood lactate, blood glucose, TT, RPE | HD, LE, OA, VL, SW, SI, CY | Significantly improved cycling TT performance by 5.1% compared to placebo. |
| Berry and Wagner [21] | “Effects of pseudoephedrine on 800-m run times of female collegiate track athletes” | 2.5 mg/kg (144 mg) | 90 | 7 | / | 13 (2 dropouts) | Female (19.6 ± 1.3) | 800-m running exercise | Aerobic | HR, TT | LD, SE, YA, LW, LI, RU | No effect on 800-m running performance. |
| Gradidge et al. [22] | “Effect of a therapeutic dose of pseudoephedrine on swimmers’ performance” | 90 mg/day | Performance was measured after a 4-day period of ingestion of PSE | 4 | / | 7 | Male and Female (44 ± 7) | 50-m sprint and 2000-m swimming exercise | Anaerobic and Aerobic | HR, TT, RPE | LD, LE, OA, SW | No major effect with regard to swimming. |
| Pritchard-Peschek et al. [24] | “Pseudoephedrine and preexercise feeding: influence on performance” | 2.8 mg/kg (204 mg) | 110 | 7 | 64.8 | 10 | Male (30.6 ± 6.6) | Approx. 30 min cycling time trial at 7 kJ/kg BM workload | Aerobic | blood lactate, TT | HD, LE, OA, VL, LW, LI, CY | No effect on cycling TT performance of approx. 30 min. |
| Pritchard-Peschek et al. [25] | “The dose-response relationship between pseudoephedrine ingestion and exercise performance” | 2.3 mg/kg or 2.8 mg/kg) (172.7 mg or 210.28 mg) | 85 | 7 | 65 | 10 | Male (26.5 ± 6.2) | Approx. 30 min cycling time trial at 7 kJ/kg BM workload | Aerobic | TT | HD, SE, YA, VH, LW, LI, CY | No effect on cycling TT performance. |
| Spence et al. [19] | “A comparison of caffeine versus pseudoephedrine on cycling time-trial performance” | 180 | 60 | 2 | 58.9 | 10 | Male (30 ± 2) | Approx. 60 min exercise (40-km cycling time trial) | Aerobic | HR, blood lactate, TT | HD, LE, OA, VL, SW, SI, CY | No significant improvement on cycling TT. |
PSE, pseudoephedrine; HR, heart rate; RPE, rate of perceived exertion; TT, time trial; s, second(s); min, minute(s); h, hour; m, metre(s); km, kilometre(s); rpm, rotations per minute; VO2 max, maximum oxygen uptake; BM, body mass. Grey shading denotes study not included in the systematic review by Trinh et al. [3]. Subgroup code (see Table 3 for quantitative details): high dose/low dose (HD/LD); long/short exercise duration (LE/SE); older/younger (OA/YA); VO2 max higher/lower (VH/VL); long washout/short washout (LW/SW); long/short pre-exercise ingestion time (LI/SI); cycling/running (CY/RU). PSE dose given as ‘mg/kg’ was converted to ‘mg’ using mean body mass of participants