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Journal of Strength and Conditioning Research, 2000, 14(2), 151–156q 2000 National Strength & Conditioning Association

Effects of Active and Passive Recovery Conditionson Blood Lactate, Rating of Perceived Exertion,and Performance During Resistance Exercise

KEITH P. CORDER, JEFFREY A. POTTEIGER, KAREN L. NAU,STEPHEN F. FIGONI, AND SCOTT L. HERSHBERGER

Department of Health, Sport, and Exercise Sciences, University of Kansas, Lawrence, Kansas 66045.

ABSTRACT

Active recovery has proven an effective means in reducingblood lactate concentration ([La2]) after various activities, yetits effects on performance are less clear. We investigated theeffects of passive and active recovery on blood [La2], ratingof perceived exertion (RPE), and performance during a re-sistance training workout. Fifteen resistance-trained malescompleted 3 workouts, each consisting of 6 sets of parallelsquat exercise performed at 85% of 10 repetition maximum(10RM). Each set was separated by a 4-minute recovery pe-riod. Recovery was randomly assigned from the following:passive sitting; pedaling at 25% of onset of blood lactate ac-cumulation (OBLA) exercise intensity (25%-OBLA); and ped-aling at 50% of OBLA exercise intensity (50%-OBLA). Activerecovery was performed on a bicycle ergometer at 70rev·min21. Performance was determined postworkout by amaximal repetition performance (MRP) squat test using 65%of 10RM. Blood samples were collected: prewarm-up; post-second, postfourth, postsixth, and MRP sets; and postsec-ond, postfourth, and postsixth recovery periods. Significantdifferences (p # 0.05) were observed in [La2], and RPEamong the 3 recoveries, with 25%-OBLA lower than passiveand 50%-OBLA. Total repetitions to exhaustion for the MRPwere: passive (24.1 6 1.8); 25%-OBLA (29.3 6 1.8); and 50%-OBLA (23.1 6 1.7), with 25%-OBLA being significantlygreater than passive and 50%-OBLA. In this investigation,active recovery at 25%-OBLA proved to be the most effectivemeans of reducing [La2] during recovery and increasing per-formance following a parallel squat workout.

Key Words: onset of blood lactate accumulation, exer-cise, training

Reference Data: Corder, K.P., J.A. Potteiger, K.L. Nau,S.F. Figoni, and S.L. Hershberger. Effects of active andpassive recovery conditions on blood lactate, rating ofperceived exertion, and performance during resistanceexercise. J. Strength Cond. Res. 14(2):151–156. 2000.

Introduction

Results obtained from past investigations indicatethat performance may be adversely affected by el-

evated blood lactate concentration ([La2]) (17, 25, 27).High-intensity muscular contractions add to both in-tramuscular and circulating levels of La2 and hydro-gen ions (H1) (11, 15) that will retard the rate of gly-colysis by inhibiting the activity of glycolytic enzymes(7) or interfere with the muscle contraction process (12,20). The removal of La2 and H1 from the active muscleand blood after high-intensity exercise is thought to becritical to subsequent peak performance (19).

There is a significant amount of literature identi-fying the positive aspects of an active recovery on La2

removal during subsequent bouts of exercise lasting15–30 minutes. Previous investigations (2, 8, 9, 11, 21)have shown that La2 removal occurs more rapidlyduring continuous aerobic recovery. Specifically, Her-mansen and Stensvold (11) found that the greatest re-ductions in blood [La2] occurred at an average of 63%of maximal aerobic power (V̇O2max). Additional in-vestigations have found that the rate of blood La2 dis-appearance is related to the intensity of the recoveryexercise with optimal removal occurring between 25%and 63% of V̇O2max (2, 8, 11).

Although the effectiveness of active recovery fol-lowing moderate-duration exercise is well documented(2, 8, 11, 24, 29), few investigations (3, 23, 30) havedetermined the impact of short duration active recov-ery (,10 minutes) on high-intensity exercise. Stamfordet al. (24) and Weltman et al. (29) found an increase inlactate clearance when using an active recovery follow-ing supramaximal and maximal exercise, respectively.Recently, Signorile et al. (23) examined performanceduring a series of 8 6-second supramaximal rides ona modified cycle ergometer separated by 30-second ac-tive or passive recovery periods. Their results indicat-ed that active recovery provides superior performanceover passive rest in repeated short-term, high-intensity

152 Corder, Potteiger, Nau, Figoni, and Hershberger

power activities. Weltman et al. (30) reported thatwhen a 1-minute cycle ergometer ride was followed byeither passive or active recovery, the active recoveryproduced significantly higher power output in a sub-sequent effort. This improved performance was attrib-uted to increased rates of La2 clearance. Bogdanis etal. (3) had subjects perform 2 maximal effort 30-secondcycle ergometer sprints, separated by 4 minutes of ei-ther active or passive recovery. Active recovery result-ed in a significantly higher mean power output duringsprint 2 compared to passive recovery.

To our knowledge, the impact of active versus pas-sive recovery on La2 metabolism and performanceduring resistance training exercise has not been re-ported. Resistance-trained athletes, such as bodybuild-ers or power-lifters, must perform exercises at maxi-mal or near maximal intensities with repeated effortsin order to enhance muscular hypertrophy and/orstrength. Recovery between efforts for these athletesmay be a critical issue for maximizing performance;however, to our knowledge no investigations have ex-amined this issue. Therefore, the purpose of this studywas to determine the effects of active and passive re-covery on blood [La2], rating of perceived exertion(RPE), and performance on a maximal test of parallelsquats.

MethodsSubjectsFifteen resistance-trained males volunteered to partic-ipate in the study. The physical characteristics (mean6 SD) of the subjects were as follows: age (23.5 6 1.3years); height (177.5 6 1.4 cm); body mass (88.3 6 2.9kg); and 10 repetition maximum in the parallel squat(150.7 6 4.8 kg). Prior to participation in the study,each subject received an explanation of the proceduresand provided written informed consent in accordancewith university guidelines for human experimentation.The criteria for acceptance as a subject included par-ticipation in a current resistance-training program atleast 3 d·wk21 for a minimum of 6 months prior tostarting the investigation and no medical contraindi-cations. During the study the subjects refrained fromconsuming any food or beverage for at least 3 hoursbefore each testing session, participating in any typeof exercise for at least 24 hours prior to each exercisetest, and participating in any type of lower extremityexercise for a minimum of 3 days prior to each exercisetest. For the duration of the study subjects were in-structed to maintain normal dietary patterns and re-frain from using any ergogenic aids.

Study DesignThere were 5 testing sessions, with each session per-formed at the same time of day for a given subject.The first session involved the collection of physicaldata and performance of a graded exercise test (GXT).

The second session was used for determination of thesubject’s 10 repetition maximum (10RM). Sessions 3–5were used for examining the influence of active andpassive recovery on blood [La2], RPE, and perfor-mance during a parallel squat workout.

GXT and Strength Testing

During the first session, subjects performed a GXT todetermine the onset of blood lactate accumulation(OBLA) and peak oxygen consumption (VO2peak) ona Monark 818E cycle ergometer. The test began at apower output of 40 W and was increased by 40 Wevery 3 minutes until subjects were unable to maintaina pedaling cadence of 70 rev·min21. Expired gaseswere collected from the subjects using a 1-way valveand analyzed for oxygen and carbon dioxide concen-trations using a Sensormedics 2900 Metabolic Mea-surement Cart (Yorba Linda, CA). The flow meter andgas analyzers were calibrated prior to each test usinga 3-L gas syringe and gases of known concentrations,respectively. Heart rate and RPE were recorded at 30seconds prior to the end of each exercise stage duringthe test with the use of a Polar heart rate telemetryunit (Polar Electro Inc., Port Washington, NY) and the10-point Borg category-ratio scale, respectively (5).Achieving any 2 of the 3 following criteria constitutedattainment of V̇O2peak: a plateau of the oxygen uptakewith an increase in power output; a respiratory ex-change ratio .1.10; and heart rate within 610beats·min21 of age-predicted maximum (22).

Fingerstick samples of blood were collected at restand during the last 30 seconds of each exercise stage.Samples were immediately analyzed for blood [La2]using a calibrated YSI 1500 Sport L-lactate analyzer(Yellow Springs, OH). For this study the OBLA wasoperationally defined as the power output correspond-ing to the 4.0 mmol·L21 blood [La2] (10). The exerciseintensity equivalent to 25% and 50% of the OBLA(25%-OBLA and 50%-OBLA) was calculated and usedduring the active recovery periods of the resistancetraining workout.

At least 48 hours after completion of the GXT, eachsubject performed a strength test to determine his10RM for the parallel squat exercise. The squat exercisewas performed using a standard Olympic barbell in asafety rack with each subject wearing a weight belt forlow back support. Proper range of motion was sig-naled to the subject when a parallel position of thefemur (midthigh) to the floor was attained. The 10RMdynamic strength test procedure was performed ac-cording to a previously described protocol (26). Verbalencouragement was provided to elicit a maximal effortfrom each subject. The heaviest mass a subject couldlift 10 times, determined to the nearest 0.5 kg, provid-ed a measure of that subject’s 10RM. From the 10RMobserved during the dynamic strength test, the resis-tance equivalent to 85% of 10RM (mean 6 SD, 128.1

Recovery and Resistance Training 153

Table 1. Blood [La2] prior to and following a resistance training workout employing different recovery conditions (N 515) (mean 6 SE).*

Condition PrewarmupPostset

2Postrec

2ac

Postset4ac

Postrec4ac

Postset6abc

Postrec6abc

Post-MRPsetabc

Passive25%-OBLA†50%-OBLA

1.3 6 0.11.4 6 0.11.2 6 0.1

4.9 6 0.44.6 6 0.34.7 6 0.3

5.4 6 0.44.5 6 0.45.1 6 0.4

6.7 6 0.55.7 6 0.46.2 6 0.5

6.7 6 0.65.6 6 0.56.2 6 0.5

7.6 6 0.66.5 6 0.56.9 6 0.5

7.7 6 0.76.2 6 0.57.1 6 0.6

9.0 6 0.58.1 6 0.48.4 6 0.4

* Within a measurement, superscript a refers to a significant difference between the passive and 25%-OBLA conditions;superscript b refers to a significant difference between the passive and 50%-OBLA conditions; and superscript c refers to asignificant difference between the 25%-OBLA and 50%-OBLA conditions (p # 0.05).

† OBLA 5 onset of blood lactate accumulation.

6 4.1 kg) was calculated and used during the parallelsquat workout.

Resistance Training WorkoutsEach subject returned to the laboratory to performeach of 3 recovery conditions during a parallel squatworkout. Each subject started the test session by rest-ing supine for a period of 10 minutes prior to the firstblood collection. After resting [La2] was determined,each subject performed 2 warm-up sets of 10 repeti-tions at 50% of 10RM. Each set was separated by 4minutes of passive recovery. After the warm up, allsubjects performed 6 sets of 10 repetitions at 85% of10RM. The 3 recovery conditions were randomly as-signed and involved the following: (a) passive recov-ery, (b) active recovery at 25%-OBLA, and (c) activerecovery at 50%-OBLA. Passive recovery (quietly sit-ting) and active recovery were performed on a Monark818E cycle ergometer. Following the last recovery pe-riod of each parallel squat workout, a maximal repe-tition performance (MRP) measure was determined byhaving the subject perform as many repetitions as pos-sible on the parallel squat exercise using 65% of his10RM (mean 6 SD, 98.0 6 3.1 kg). This test has beenused previously as a measure of resistance trainingperformance (28). The subjects were instructed tomaintain a constant up-down, no-rest cadence untilthey could no longer successfully complete a repeti-tion.

Blood [La2] was determined from fingerstick bloodsamples collected: prewarm-up; postsecond, post-fourth, postsixth, and MRP sets; and postsecond, post-fourth, and postsixth recovery periods. All blood wasanalyzed using a calibrated YSI 1500 Sport L-lactateanalyzer. Within the 4-minute recovery period, bloodsamples were collected via fingerstick within 30 sec-onds after completion of each set and within 30 sec-onds prior to the end of each rest period. Blood sam-ples during active recovery sessions were collectedwhile the subjects were pedaling. An RPE using the10-point Borg ratio scale (5) was determined at eachblood collection point. Each subject then returnedwithin 4–7 days to complete the next testing session.

All 3 testing sessions were completed within a 2-weekperiod.

Data AnalysisIn order to determine the appropriate number of sub-jects to include in this study, a priori power analysiswas conducted. Assuming a 2-tailed a of 0.05, a de-sired level of power of at least 0.80, and an effect sizeof 0.92, the required sample was approximately 15subjects (6). Prior to performing the statistical analy-ses, the assumption of sphericity under repeated-mea-sures analysis of variance (ANOVA) was tested.Huynh–Feldt e values ranged from 0.74 to 1.09 for theANOVAs, indicating that all assumptions necessary forthe use of repeated-measures ANOVA were met (13).Repeated-measures 2-way ANOVA, with La2 and RPEas the within-subjects factors and type of recovery asthe between-subjects factor, were conducted. Paired t-tests were used to identify mean differences. No cor-rection for multiple hypothesis testing was requiredbecause in the specific case when the number of con-ditions equals 3, a significant omnibus F-ratio itselfprovides a strong control for the experimentwise errorrate (18). Pearson correlation coefficients were used toestablish the relationship between [La2] and RPE ver-sus the number of repetitions performed during theMRP. An a level of 0.05 was set for all statistical test-ing. All results are reported as mean 6 SEM.

Results

The subjects in this investigation had a V̇O2peak onthe cycle ergometer of 41.9 6 6.2 ml·kg21·min21. Thepower output at 25%-OBLA was 45.9 6 9.1 W and at50%-OBLA was 73.4 6 14.6 W. The oxygen uptake val-ues for the subjects were 6.9 6 1.3 ml·kg21·min21 and13.8 6 2.5 ml·kg21·min21 for recovery at 25%-OBLAand 50%-OBLA, respectively.

Blood [La2] among the 3 conditions of passive re-covery, 25%-OBLA, and 50%-OBLA are shown in Table1. Across all conditions, there was a significant in-crease in [La2] over time. Additionally, the conditionby linear trend for the [La2] interaction was signifi-

154 Corder, Potteiger, Nau, Figoni, and Hershberger

Table 2. Ratings of perceived exertion (RPE) prior to, during, and following a resistance training workout employingdifferent recovery conditions (N 5 15) (mean 6 SEM).*

Condition PrewarmupPostset

2Postrec

2bc

Postset4c

Postrec4c

Postset6ac

Postrec6abc

Post-MRPsetc

Passive25%-OBLA†50%-OBLA

000

2.5 6 0.32.4 6 0.32.5 6 0.3

2.0 6 0.22.0 6 0.22.6 6 0.3

4.5 6 0.44.2 6 0.25.0 6 0.3

3.7 6 0.33.6 6 0.24.4 6 0.3

6.7 6 0.35.8 6 0.47.1 6 0.3

5.9 6 0.34.9 6 0.46.7 6 0.4

9.5 6 0.19.3 6 0.29.7 6 0.2

* Within a measurement, superscript a refers to a significant difference between the passive and 25%-OBLA conditions;superscript b refers to a significant difference between the passive and 50%-OBLA conditions; and superscript c refers to asignificant difference between the 25%-OBLA and 50%-OBLA conditions (p # 0.05).

† OBLA 5 onset of blood lactate accumulation.

Table 3. Pearson correlation coefficients for postrecovery6 [La2], postrecovery 6 ratings of perceived exertion (RPE),and a maximal repetition performance (MRP) measures fol-lowing resistance training workouts using 3 different recov-ery conditions (N 5 15).

Condition

[La2]versusRPE

[La2]versus

performance

RPEversus

performance

Passive25%-OBAL†50%-OBLA

0.3020.07

0.46

20.72*20.70*20.65*

20.220.05

20.48

* p # 0.01.† OBLA 5 onset of blood lactate accumulation.

cant, showing that the conditions differed in the rateby which [La2] increased. No significant mean differ-ences in [La2] were found in the prewarm-up or post-set 2 time points; however, for the other sets and re-covery periods, a significant omnibus F-ratio indicatedthe presence of at least 1 significant difference amongthe 3 conditions. The most frequent significant differ-ence in [La2] occurred between the passive and 25%-OBLA conditions, with subjects in the passive condi-tion having the higher [La2] (Table 1). This was truefor [La2] in postrecovery 2 through the post-MRP timepoints. Also, for [La2] in postrecovery 2 through thepost-MRP time points, a significant difference oc-curred between 25%-OBLA and 50%-OBLA condi-tions, with subjects in the 50%-OBLA condition havingthe higher [La2]. Only in postset 6, postrecovery 6, andthe post-MRP time points did the passive and 50%-OBLA conditions differ significantly (subjects engagedin passive recovery had higher levels of lactate). Whenengaged in either of the active recovery conditions, es-pecially at 25%-OBLA, subjects tended to have lowerlactate levels than when engaged in passive recovery.

Significant differences in RPE among the 3 condi-tions of passive recovery, 25%-OBLA, and 50%-OBLAare shown in Table 2. Additionally, the condition bylinear trend for the RPE interaction was also signifi-cant, showing that the conditions differed in the rateby which the RPEs increased. No significant differ-ences in RPE were found between the prewarm-up orpostset 2 time points; however, for the other timepoints, a significant omnibus F-ratio indicated thepresence of at least 1 significant difference among the3 conditions. Significant mean differences in RPE oc-curred between the passive and 25%-OBLA conditionsin postset 6 through the post-MRP time points, withpassive recovery showing a higher RPE. Significantmean differences in RPE also occurred between thepassive and 50%-OBLA conditions in postrecovery 2and postrecovery 6, with passive recovery having alower RPE. Finally, in postrecovery 2 through the post-recovery 6 time points, the RPE for the 25%-OBLAcondition was significantly lower than the RPE for the

50%-OBLA condition. Thus, the RPE was higher over-all for the 50%-OBLA condition, followed by the pas-sive condition, with RPEs lowest for the 25%-OBLAcondition.

A significant difference was found in the MRP test.The results of the followup-dependent t-tests indicatethat MRP was significantly higher in the 25%-OBLAcondition in comparison to the other 2 conditions.There was no significant difference between passiverecovery and 50%-OBLA condition. The MRP mea-sures for each of the recovery conditions were as fol-lows: passive (24.1 6 1.8 reps), 25%-OBLA (29.3 6 1.8reps), and 50%-OBLA (23.1 6 1.7 reps).

Correlation coefficients for postrecovery 6 [La2],postrecovery 6 RPE, and MRP for each of the 3 recov-ery conditions are shown in Table 3. A significant, neg-ative correlation was observed between the postrecov-ery 6 [La2] and the MRP measure. Not surprisingly,the lower the [La2] prior to the MRP, the higher themaximal number of repetitions possible. No significantrelationships were found in any of the conditions be-tween the postrecovery 6 [La2] time point and RPE,nor between postrecovery 6 RPE time point and theMRP measure.

Recovery and Resistance Training 155

Discussion

The primary question in the present study was wheth-er or not active recovery decreased La2 accumulationbetween sets of parallel squat exercises. The resultsfrom the present investigation indicate that lactate ac-cumulation was decreased when low-intensity exercisewas employed during the recovery periods betweensets (Table 1). The present data reveal that the mosteffective strategy for decreasing lactate accumulationwas to perform active recovery at 25% of the OBLA;recoveries using passive rest and active recovery at50% of the OBLA were significantly less effective. Italso appears that [La2] decreases during each recoveryperiod compared to the exercise set just prior to it dur-ing the 25%-OBLA condition only (Table 1). The ob-servation that the rate of lactate removal facilitated bythe performance of active recovery has been observedpreviously (8, 9, 21). The data in the present investi-gation are in agreement with several other studies in-volving the use of active recovery (1, 11, 24, 29, 30).The blood lactate concentration is a balance betweenthe removal and the production of lactate (2, 4, 8, 9,14). Alterations in blood [La2] during exercise aretherefore the net result of the simultaneous, but notnecessarily proportional, changes in the productionand/or removal of La2. While the mechanism for en-hanced La2 disappearance during active recoveryfrom strenuous exercise is unknown, the oxidation ofLa2 within the exercising skeletal muscle may be a ma-jor mechanism for lactate clearance (9, 30). Gisolfi etal. (9) suggest that the increased clearance rate of La2

during active recovery was probably a result of morerapid distribution of lactate to the liver for oxidationor reconversion to glycogen, increased utilization oflactate by the cardiac muscle, and increased utilizationof lactate by active and inactive skeletal muscles.

Another important finding in the present investi-gation was the high relationship between elevatedblood [La2] and subsequent exercise performance. Asexpected, there was an increase in [La2] following sets2, 4, and 6. Moreover, the blood [La2] postset 6 dif-fered significantly between conditions and was nega-tively correlated with the [La2] and the maximal rep-etitions performed (Table 3). These data indicate thatsubjects with higher [La2] performed fewer repetitionson the maximal repetition performance test. Thesefindings are in agreement with previous studies (17,27), in that work performance is inhibited and musclefatigue occurs when blood [La2] is elevated due to pri-or exercise. Bogdanis et al. (3) suggest there are at least4 mechanisms that may explain the performance im-provement after active recovery: a greater creatine-phosphate resynthesis; a lower muscle [La2] and [H1];an increased contribution of aerobic metabolism to en-ergy supply; and nonmetabolic factors. Hermansenand Stensvold (11) observed that an increased activity

of the working muscles would increase the efflux ofLa2 from the exercising tissue. This increased activityduring recovery, especially if it was of low intensity,should enhance performance because of the increasedLa2 and H1 efflux from the working muscles and de-creased intracellular [H1]. This increased activity dur-ing recovery should allow the working tissues to con-tinue performing in an optimal cellular environment.

Failure to consider the individual differences for anoptimal recovery exercise intensity with respect toeach subject’s OBLA could possibly shift the balanceto a greater production of lactate. In the present study,in order to precipitate an optimal lactate eliminationresponse, individual OBLA were determined using aGXT. According to Heck et al. (10), a maximal steadystate was found at a lactate value of 4.02 mmol·L21. Byobserving the exercise intensity at the 4.0 mmol·L21

blood [La2], we were able to individualize each sub-ject’s recovery intensities. The power outputs used inthe current study were ;46 W and ;74 W for 25%-OBLA and 50%-OBLA, respectively. These values, rel-ative to the OBLA, are within the previously reportedoptimal values for active recovery (2, 4, 8). At exerciseintensities greater than the OBLA, there will be an im-balance between the rates of La2 production and clear-ance, and as a result, La2 will progressively accumu-late in the blood (16). Therefore, if the OBLA of anathlete is evaluated, and the resulting information isto be applied to the training regime, an effective andsafe means to performance enhancement can be pro-duced.

A finding of interest in this investigation is thevariation of significant mean differences in RPEthroughout the workout sets. As indicated in Table 2,significant differences in RPE occurred between thepassive and 25%-OBLA conditions in postset 6through post-MRP time points and between the pas-sive and 50%-OBLA conditions in postset 3 and post-recovery 6. Additionally, in postrecovery 2 throughpostrecovery 6, the RPE for the 25%-OBLA conditionwas significantly lower than the RPE for the 50%-OBLA condition. Thus, the RPE was higher overall forthe 50%-OBLA condition. These data indicate a re-duced perception of effort during exercise at lowerintensity compared to passive and higher intensityrecovery. Although there were significant differencesbetween the recovery conditions, no significant corre-lations were observed between postrecovery 6 RPEand MRP within each of the 3 recovery conditions.

In summary, the present study demonstrated thatlower-intensity active recovery effectively minimizedLa2 accumulation compared to passive or higher-in-tensity active recovery. The data strongly support theview that the elimination of La2 occurs using low-in-tensity active recovery following intense resistance ex-ercise and is associated with improved endurance per-formance in the squat exercise.

156 Corder, Potteiger, Nau, Figoni, and Hershberger

Practical Applications

When attempting to improve large muscle resistancetraining performance an active recovery between setsshould be used. The improvement in performance islikely due to a decrease in lactate accumulation duringrecovery. Based on the data from this investigation itappears that exercise at 25% of the power elicited at ablood lactate concentration of 4.0 mmol·L21 is betterthan passive recovery or exercise at 50% of the powerelicited at a 4.0 mmol·L21 blood lactate concentration.Strength and conditioning professionals and athletesshould identify this exercise intensity through testingand then incorporate an active recovery scheme intotheir training workout.

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