Body composition changes affect energy cost of running during 12 months of specific diet and training in amateur athletes.

Considering the relation between body weight composition and energy cost of running, we tested the hypothesis that by modifying body composition by means of a combined protocol of specific diet and training, the energy cost of motion (Cr) may be reduced. Forty-five healthy and normal-weight subjects were divided into 3 groups that performed a different treatment: the first group attended a dietary protocol (D), the second group participated in a running program (R), and the third group followed both the dietary and running protocols (R&D). Each subject underwent 3 anthropometric and exercise evaluation tests during 1 year (at entry (T0), month 6 (T6), and month 12 (T12)) to assess body composition and Cr adjustments. The mean fat mass (FM) values were reduced in R&D from 12.0 ± 4.0 to 10.4 ± 3.0 kg (p < 0.05 T0 vs. T12) and in the D group from 14.2 ± 5.8 to 11.6 ± 4.7 kg (p < 0.05 T0 vs. T12). Conversely, the mean fat free mass values increased in R&D (from 56.3 ± 8.8 to 58.3 ± 9.8 kg, p < 0.05 T0 vs. T12) and in the D group (from 50.6 ± 13.2 to 52.9 ± 13.6 kg, p < 0.05 T0 vs. T12). The mean Cr values of the 2 groups were significantly modified throughout the 1-year protocol (1.48 ± 0.16 and 1.40 ± 0.15 kcal·kg(-b)·km(-1) in the R&D group at T0 and T12, respectively; 1.83 ± 0.17 and 1.76 ± 0.23 kcal·kg(-b)·km(-1) in D group at T0 to T12, respectively). The R&D and D groups that underwent the diet protocol had a positive change in body composition during the year (FM/fat free mass ratio decline), which determined a Cr reduction.

Physiological responses and energy expenditure during competitive fencing.

Fencing is an Olympic sport in which athletes fight one against one using bladed weapons. Contests consist of three 3-min bouts, with rest intervals of 1 min between them. No studies investigating oxygen uptake and energetic demand during fencing competitions exist, thus energetic expenditure and demand in this sport remain speculative. The aim of this study was to understand the physiological capacities underlying fencing performance. Aerobic energy expenditure and the recruitment of lactic anaerobic metabolism were determined in 15 athletes (2 females and 13 males) during a simulation of fencing by using a portable gas analyzer (MedGraphics VO2000), which was able to provide data on oxygen uptake, carbon dioxide production and heart rate. Blood lactate was assessed by means of a portable lactate analyzer. Average group energetic expenditure during the simulation was (mean ± SD) 10.24 ± 0.65 kcal·min(-1), corresponding to 8.6 ± 0.54 METs. Oxygen uptakeand heart rate were always below the level of anaerobic threshold previously assessed during the preliminary incremental test, while blood lactate reached its maximum value of 6.9 ± 2.1 mmol·L(-1) during the final recovery minute between rounds. Present data suggest that physical demand in fencing is moderate for skilled fencers and that both aerobic energy metabolism and anaerobic lactic energy sources are moderately recruited. This should be considered by coaches when preparing training programs for athletes.