A multicenter study on the relative effectiveness of a 12-week physical training program for adults with an oncologic diagnosis.

PURPOSE: The purpose of this study was to examine the association between cancer survivors' socio-demographic and clinical characteristics and aerobic fitness changes following a physical training program. METHODS: We assessed the association between participant's characteristics and aerobic fitness in the six-min walk test (6MWT) after a 12-week LIVESTRONG® at Young Men's Christian Association (YMCA) exercise program for adults with an oncologic diagnosis using linear mixed effects models. RESULTS: Fifty-one percent of participants had a breast cancer diagnosis and 22 % had received treatment within 1 year of enrollment. At baseline, participants who reported good/excellent health status performed better in the 6MWT than those who reported poor/fair health status (384.2 vs. 345.0 m, p = 0.035). After 12 weeks, all participants increased their average 6MWT performance by 54.2 m. After adjustment for age, gender, physical activity level, and smoking status, participants who were 60 years old or younger had a greater increase in the 6MWT score than participants older than 60 years (63.2 vs. 43.9 m, p = 0.041) while those who had never been YMCA members had a greater increase in the 6MWT compared to those who had ever been a YMCA member (62.2 vs. 40.3 m, p = 0.041). CONCLUSION: Overall, aerobic fitness among adults with an oncologic diagnosis increased after a 12-week exercise program, particularly among participants who were 60 years old or younger or were not YMCA members at enrollment. Participants with poorer health had lower aerobic fitness at baseline, though they had a similar positive response to the program as healthier participants. Future study designs may include randomization and an additional untreated arm.

Physiological and psychological responses to outdoor vs. laboratory cycling.

The purpose of this study was to determine the physiological and psychological responses to laboratory vs. outdoor cycling. Twelve recreationally trained male cyclists participated in an initial descriptive testing session and 2 experimental trials consisting of 1 laboratory and 1 outdoor session, in a randomized order. Participants were given a standardized statement instructing them to give the same perceived effort for both the laboratory and outdoor 40-km trials. Variables measured include power output, heart rate (HR), core temperature, skin temperature, body weight, urine specific gravity (USG), Rating of Perceived Exertion (RPE), attentional focus, and environmental conditions. Wind speed was higher in the outdoor trial than in the laboratory trial (2.5 ± 0.6 vs. 0.0 ± 0.0 m·s-1, p = 0.02) whereas all other environmental conditions were similar. Power output (208.1 ± 10.2 vs. 163.4 ± 11.8 W, respectively, p < 0.001) and HR (152 ± 4 and 143 ± 6 b·min-1, respectively, p = 0.04) were higher in the outdoor trial than in the laboratory trial. Core temperature was similar, whereas skin temperature was cooler during the outdoor trial than during the laboratory trial (31.4 ± 0.3 vs. 33.0 ± 0.2° C, respectively, p < 0.001), thus creating a larger thermal gradient between the core and skin outdoors. No significant differences in body weight, USG, RPE, or attentional focus were observed between trials. These data indicate that outdoor cycling allows cyclists to exercise at a higher intensity than in laboratory cycling, despite similar environmental conditions and perceived exertion. In light of this, cyclists may want to ride at a higher perceived exertion in indoor settings to acquire the same benefit as they would from an outdoor ride.

The performance effect of early versus late carbohydrate feedings during prolonged exercise.

The purpose of this study was to determine how the timing of isoenergetic carbohydrate feedings during prolonged cycling affects performance in a subsequent 10-km cycling time trial. Recreationally trained male cyclists (n = 8; age, 34.5 ± 8.3 years; mass, 80.0 ± 6.3 kg; body fat, 16.0% ± 3.8%, peak oxygen uptake, 4.54 ± 0.42 L·min(-1)) completed 4 experimental trials consisting of cycling continuously for 2 h at 62.4% ± 1.9% of peak oxygen uptake, followed immediately by a self-paced 10-km time trial. The 4 conditions included no carbohydrate ingestion (PP), early carbohydrate ingestion (CP), late carbohydrate ingestion (PC), or carbohydrate ingestion throughout (CC). Blood samples were obtained at 0, 60, and 120 min of cycling as well as at the conclusion of the time trial. The 10-km time trial time to completion was faster in trials CC (17.70 ± 0.52 min) and PC (17.60 ± 0.62 min) as compared with trial PP (18.13 ± 0.52 min, p = 0.028 and p = 0.007, respectively) while trial CP (17.85 ± 0.58 min, p = 0.178) was not. Serum glucose increased with carbohydrate feedings (p < 0.05), while serum free fatty acid concentrations were lower in trials PC and CC than trials CP and PP (p < 0.05). There was no difference in oxygen uptake, heart rate, rating of perceived exertion, or substrate use between trials (p > 0.05). These data indicate that carbohydrate ingestion throughout or late during a 2-h cycling bout can improve subsequent 10-km time trial performance.