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Katrien De Bock, Bert O. Eijnde, Monique Ramaekers, and Peter Hespel

Purpose:

The purpose of this study was to investigate the effect of acute and 4-week Rhodiola rosea intake on physical capacity, muscle strength, speed of limb movement, reaction time, and attention.

Methods:

PHASE I: A double blind placebo-controlled randomized study (n = 24) was performed, consisting of 2 sessions (2 days per session). Day 1: One hour after acute Rhodiola rosea intake (R, 200-mg Rhodiola rosea extract containing 3% rosavin + 1% salidroside plus 500 mg starch) or placebo (P, 700 mg starch) speed of limb movement (plate tapping test), aural and visual reaction time, and the ability to sustain attention (Fepsy Vigilance test) were assessed. Day 2: Following the same intake procedure as on day 1, maximal isometric knee-extension torque and endurance exercise capacity were tested. Following a 5-day washout period, the experimental procedure was repeated, with the treatment regimens being switched between groups (session 2). PHASE II: A double blind placebo-controlled study (n = 12) was performed. Subjects underwent sessions 3 and 4, identical to Phase I, separated by a 4-week R/P intake, during which subjects ingested 200 mg R/P per day.

Results:

PHASE I: Compared with P, acute R intake in Phase I increased 0 < -05) time to exhaustion from 16.8 ± 0.7 min to 17.2 ± 0.8 min. Accordingly, VO2peak (p < .05) and VCO2peak(p< .05) increased during R compared to P from 50.9 ± 1.8 ml • min-1 • kg−1 to 52.9 ± 2.7 ml • min-1 • kg"’ (VO2peak) and from 60.0 ± 2.3 ml • min-1 • kg-’ to 63.5 ± 2.7 ml • min-1 kg-1 (VCO2peak). Pulmonary ventilation (p = .07) tended to increase more during R than during P(P: 115.9±7.7L/min; R: 124.8 ± 7.7 L/min). All other parameters remained unchanged. PHASE II: Four-week R intake did not alter any of the variables measured.

Conclusion:

Acute Rhodiola rosea intake can improve endurance exercise capacity in young healthy volunteers. This response was not altered by prior daily 4-week Rhodiola intake.

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Evelien Van Roie, Christophe Delecluse, Joke Opdenacker, Katrien De Bock, Eva Kennis, and Filip Boen

Two groups of sedentary older adults, participating in either a lifestyle physical activity intervention (LIFE, n = 60) or a structured exercise intervention (STRU, n = 60), were compared with a control group (CO, n = 66) in terms of physical fitness and cardiovascular risk factors. Participants in LIFE were stimulated to integrate physical activity into their daily routines and received an individualized home-based program. Participants in STRU completed 5 supervised training sessions every 2 wk in a fitness center. Both interventions lasted 11 months and focused on endurance, strength, flexibility, and postural/balance exercises. The results revealed that the interventions were equally effective in improving functional performance. STRU was more effective than LIFE in improving cardiorespiratory and muscular fitness. Limited effects emerged on cardiovascular risk, with STRU improving in total cholesterol and HDL. Consequently, interventions aiming at reducing cardiovascular risks among sedentary elderly should focus on long-term changes in physical activity behavior.