Incidence of nonresponse and individual patterns of response following sprint interval training

Abstract

The current study sought to explore the incidence of nonresponders for maximal or submaximal performance following a variety of sprint interval training (SIT) protocols. Data from 63 young adults from 5 previously published studies were utilized in the current analysis. Nonresponders were identified using 2 times the typical error (TE) of measurement for peak oxygen uptake (2 × TE = 1.74 mL/(kg·min)), lactate threshold (2 × TE = 15.7 W), or 500 kcal time-to-completion (TTC; 2 × TE = 306 s) trial. TE was determined on separate groups of participants by calculating the test-retest variance for each outcome. The overall rate of nonresponders for peak oxygen uptake across all participants studied was 22% (14/63) with 4 adverse responders observed. No nonresponders for peak oxygen uptake were observed in studies where participants trained 4 times per week (n = 18), while higher rates were observed in most studies requiring training 3 times per week (30%-50%; n = 45). A nonresponse rate of 44% (8/18) and 50% (11/22) was observed for the TTC test and lactate threshold, respectively. No significant correlations were observed between the changes in peak oxygen uptake and TTC (r = 0.014; p = 0.96) or lactate threshold (r = 0.17; p = 0.44). The current analysis demonstrates a significant incidence of nonresponders for peak oxygen uptake and heterogeneity in the individual patterns of response following SIT. Additionally, these data support the importance of training dose and suggest that the incidence of nonresponse may be mitigated by utilizing the optimal dose of SIT.

Inter-Individual Variability in the Adaptive Responses to Endurance and Sprint Interval Training: A Randomized Crossover Study

“…Consistent with previous observations of heterogeneity in the individual response to END [7,32,33,37] and SIT [8,9] we have also observed significant rates of non-response following both END and SIT in the current study (Fig 4). The present finding that END and SIT elicited similar rates of non-response for VO 2 peak, lactate threshold, and submaximal HR agrees with previous observations that END and SIT Importantly, while inter-individual variability in the response to training has been repeatedly demonstrated [7,33,37], attempts to quantify individuals as responders or non-responders are relatively recent [5–9,32,38].…”

“…While variability in the individual responses to END is established [2,6,7,19,32,33], we recently demonstrated similar variability in response to the SIT protocol utilized in the present study [9]. The major novel finding of the current study is our demonstration of variability in the individual responses following different training protocols (END and SIT).…”

“…In order to determine typical error (TE) for VO 2 peak, lactate threshold and submaximal HR, a supplemental experiment involving eight recreationally active participants (four males; four females, age, 21±1 yrs; BMI, 21±2 kg/m 2 ; VO 2 peak, 44±6 mL/kg/min) reported to the lab on two separate occasions separated by at least a week as described previously [9]. On each visit to the lab participants performed identical incremental ramp tests to volitional fatigue as described above.…”

“…Specifically, VO 2 peak can increase [2,4], decrease [5], or remain unchanged [6,7] following structured endurance training (END). Similarly, inter-individual variability in training responses have also been observed following supra-maximal sprint interval training (SIT) [8,9]. While variability in training responses has been demonstrated following both END and SIT, it is currently unknown whether individuals who fail to respond following one type of exercise training might respond to a different training stimulus (i.e.…”

The effects of dietary nitrate supplementation on the adaptations to sprint interval training in previously untrained males

“…Nevertheless, plasma 261 nitrite concentration was higher in the NIT group prior to the SIT sessions compared to the 262 PLA group suggesting the supplementation regimen was still sufficient to increase NO 263 availability. It must also be recognised that there is a well-established heterogeneity in response 264 to exercise training 24 and SIT 25,26 . This variability in individual response makes it challenging 265 to detect an additional effect of a supplement beyond that of the exercise training.…”