
280 S.E.2d 759 (1981)
Lynn R. JOHNSON
v.
Robert DUNLAP and Racing, Inc. d/b/a Rainbow Speedway.
No. 8118SC25.
Court of Appeals of North Carolina.
August 4, 1981.
*762 Younce, Wall & Chastain by Percy L. Wall and Peter Chastain, Greensboro, for plaintiff-appellant.
Nichols, Caffrey, Hill, Evans & Murrell by William D. Caffrey and Eugene W. Purdom, Greensboro, for defendants-appellees.
CLARK, Judge.
The trial court erred in granting the judgment N.O.V., and the judgment must be reversed and a new trial ordered.
The defendants' motion for directed verdict and motion for judgment N.O.V. did not state the specific grounds therefor as required by G.S. 1A-1, Rule 50(a). Both the North Carolina Supreme Court and the Court of Appeals have stated that this requirement is mandatory. Anderson v. Butler, 284 N.C. 723, 202 S.E.2d 585 (1974), and Wheeler v. Denton, 9 N.C.App. 167, 175 S.E.2d 769 (1970). But the Supreme Court has stated: "However, the courts need not inflexibly enforce the rule when the grounds for the motion are apparent to the court and the parties." Anderson v. Butler, 284 N.C. at 729, 202 S.E.2d at 588. Further, the plaintiff did not object at trial to the failure of the motion to state specific grounds. Having failed to so object, the plaintiff cannot raise the issue on appeal. Builders Supplies Co. v. Gainey, 10 N.C.App. 364, 178 S.E.2d 794, cert. denied, 278 N.C. 300, 180 S.E.2d 178 (1971); Pergerson v. Williams, 9 N.C.App. 512, 176 S.E.2d 885 (1970).
Under the circumstances we consider on its merits the trial court's granting of the judgment N.O.V. in favor of defendants. A motion for judgment N.O.V. is a motion that judgment be entered in accordance with the movants' earlier motion for a directed verdict and notwithstanding the contrary verdict actually returned by the jury. Hensley v. Ramsey, 283 N.C. 714, 199 S.E.2d 1 (1973). Though no specific grounds were stated for either the motion for directed verdict or motion for judgment N.O.V., motions under Rule 50 are designed to test the sufficiency of the evidence. It is apparent to this Court, and should be to the parties, that the trial court granted the judgment N.O.V. on the ground that defendants by their evidence had established the due execution of either one or both of the releases and that plaintiff had failed to offer sufficient evidence that he did not validly execute the 25 August 1973 and the 25 September 1973 releases.
The defendants having pled the releases in bar of plaintiff's claim, they had the burden of proof. A directed verdict, or a judgment N.O.V., can be granted for the party having the burden of proof only where the credibility of movant's evidence is manifest as a matter of law. Bank v. Burnette, 297 N.C. 524, 256 S.E.2d 388 (1979). See Note, Directing a Verdict in Favor of the Party with the Burden of Proof, 16 Wake Forest L.Rev. 607 (1980).
Though waiver is not allowed as a defense by reply under G.S. 1A-1, Rule 7, and not raised in or considered by the trial court or argued in the briefs on appeal, it is manifest from defendants' own evidence that their rights under the 25 August 1973 release were waived when they presented to and had plaintiff execute the 25 September 1973 release and paid to him the sum of $1500.00 provided therein. See 13 Strong's N.C. Index 3d Waiver § 2 (1978). Waiver is a matter of law to be determined by the court where the facts are not disputed. Builders v. Gadd, 183 N.C. 447, 111 S.E. 771 (1922). The provisions of a contract (release) may be waived by intentionally relinquishing a known right, advantage, or benefit, and such intention to waive may be expressed or implied from acts or conduct naturally leading the other party to believe that the right has been relinquished. Klein v. Insurance Co., 289 N.C. 63, 220 S.E.2d 595 (1975); Fetner v. Granite Works, 251 N.C. 296, 111 S.E.2d 324 (1959); Lithographic Co. v. Mills, 222 N.C. 516, 23 S.E.2d 913 (1943).
*763 Assuming, arguendo, that there was no waiver of the 25 August 1973 release, the plaintiff offered ample evidence that he did not see and did not knowingly and voluntarily execute the release or that it was vitiated by fraud or mistake. Though plaintiff's signature appears on the release, his testimony that he had never seen it is supported by testimony that his two companions signed what appeared to be a legal pad on a clipboard at the pit gate when plaintiff signed, yet their signatures were not on the release offered in evidence by defendants. Further, all the evidence tends to show that some 300 signatures were obtained by several pit area attendants as the cars were lined up at the pit gate for admission. The jury could find from this evidence that plaintiff had never seen the release or that the circumstances were such that he was not given an opportunity to read it. Releases which exculpate persons from liability for negligence are not favored by the law. Jordan v. Storage Co., 266 N.C. 156, 146 S.E.2d 43 (1966); see Annot., 175 A.L.R. 8 (1948).
It is also manifest that plaintiff's evidence was sufficient to show mental incompetency at the time he executed the release in the hospital on 25 September 1973 or that the consideration was grossly inadequate. See 12 Strong's N.C. Index 3d Torts § 7.2 (1978).
Defendants joined with their motion for judgment N.O.V. a motion for a new trial in the alternative as allowed by G.S. 1A-1, Rule 50(b)(1). The stated grounds for the new trial motion, as required by Rule 59(a), were all incorporated and adopted in the judgment entered by the trial court, as follows: (1) the jury verdict appears to have been given under the influence of passion and prejudice, (2) there is insufficient evidence to justify the jury verdict, (3) the jury verdict is contrary to the evidence, and (4) justice and equity require a new trial.
G.S. 1A-1, Rule 59(a) lists eight specific grounds for granting a new trial and one "catch-all" ground, Rule 59(a)(9), "any other reason heretofore recognized as grounds for a new trial." The only ground listed in the judgment specifically provided for by Rule 59 is insufficiency of the evidence, and we have found that the evidence was sufficient to support the verdict. The other three grounds in the judgment came within the "catch-all" Rule 59(a)(9). We do not find it necessary to determine whether the grounds "passion and prejudice" of the jury and "justice and equity" are grounds "heretofore recognized" in this State. The ground "contrary to the evidence" has been so recognized and interpreted as giving to the trial judges broad discretionary authority to set aside a verdict and order a new trial. No issue of law is raised, and the ruling is not reviewable on appeal in the absence of manifest abuse of discretion. Britt v. Allen, 291 N.C. 630, 231 S.E.2d 607 (1977). While we find little in the record on appeal in support of the stated "contrary to the evidence" ground, we do not find a manifest abuse of discretion.
The judgment N.O.V. is reversed and the cause is remanded for a
New trial.
ROBERT M. MARTIN and HILL, JJ., concur.
